Статті в журналах з теми "Friction joint"
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1
Tanaka, E., N. Kawai, M. Tanaka, M. Todoh, T. van Eijden, K. Hanaoka, D. A. Dalla-Bona, T. Takata, and K. Tanne. "The Frictional Coefficient of the Temporomandibular Joint and Its Dependency on the Magnitude and Duration of Joint Loading." Journal of Dental Research 83, no. 5 (May 2004): 404–7. http://dx.doi.org/10.1177/154405910408300510.
Повний текст джерелаАнотація:
In synovial joints, friction between articular surfaces leads to shear stress within the cartilaginous tissue, which might result in tissue rupture and failure. Joint friction depends on synovial lubrication of the articular surfaces, which can be altered due to compressive loading. Therefore, we hypothesized that the frictional coefficient of the temporomandibular joint (TMJ) is affected by the magnitude and duration of loading. We tested this by measuring the frictional coefficient in 20 intact porcine TMJs using a pendulum-type friction tester. The mean frictional coefficient was 0.0145 (SD 0.0027) after a constant loading of 50 N during 5 sec. The frictional coefficient increased with the length of the preceding loading duration and exceeded 0.0220 (SD 0.0014) after 1 hr. Application of larger loading (80 N) resulted in significantly larger frictional coefficients. In conclusion, the frictional coefficient in the TMJ was proportional to the magnitude and duration of joint loading.
2
Senthilkumar, M., Lavish Kumar Singh, S. Lakshmanan, A. M. Shanawaz, and M. Selwin. "Study of the Effect on Friction Welded Surface on Copper Aluminium Juncture." Key Engineering Materials 935 (November 30, 2022): 93–98. http://dx.doi.org/10.4028/p-48f907.
Повний текст джерелаАнотація:
The economical and highly productive method of welding is used to join a dissimilar material. The quality of welded joint with high efficiency is obtained from friction welding process. The intention of the current work is to assess the progress of solid state juncture of dissimilar materials of aluminum 6082 and copper. The strong joints were developed using frictional heat and external pressure. The friction welded joints were tested under welding strength and surface analysis using scanning force microscopy (SFM). Rotational speed, friction pressure and forging pressure were used to evaluate the performance of the welded joints. Optimize the welding strength and hardness was attained through taguchi method.
3
Brodny, Jarosław. "ANALYSIS OF OPERATION OF ARCH FRICTIONAL JOINT LOADED WITH THE IMPACT OF FREELY FALLING MASS." Studia Geotechnica et Mechanica 35, no. 1 (March 1, 2013): 59–71. http://dx.doi.org/10.2478/sgem-2013-0005.
Повний текст джерелаАнотація:
Abstract Yielding support, commonly applied to secure dog headings, is made of carrying elements in the form of steel frames and friction props. Yielding capacity of this support is realized in frictional joints, which due to their geometry can be divided to straight and arch joints. Occurring in steel frames arch frictional joints are characterized with more complex loading state than straight joints used in friction props. In the article, there is presented an analysis of the state of stress and deformation of the arch frictional joint, which was carried out on the model of these joints using finite element method. The scope of the analysis included two methods of loading of arch frictional joint, namely its axial compression and bending. In both cases, joints were loaded dynamically with the impact of freely falling mass. Arch joints with and without passive pressure were submitted to an axial compression. Physical model of the frictional joint was developed on the basis of a system applied during the stand tests. To solve mathematical model an explicit integration method was used. As a result of analyses carried out, temporal courses of force transmitted through the frictional joint, and displacements of section sliding down were determined. On the basis of the temporal courses, dependences between maximum value of force transmitted through the frictional joint and the height from which the impact mass falls down were determined. Distributions of reduced stresses in elements of frictional joint were also determined and the state of deformation was described. In order to emphasize the difference between straight and arch frictional joints, also an analysis of internal forces in arch frictional joint depending on its geometrical parameters without and with passive pressure was presented.
4
Han, Qingkai, Xueyan Zhao, Xingxiu Li, and Bangchun Wen. "Bifurcations of a Controlled Two-Bar Linkage Motion with Considering Viscous Frictions." Shock and Vibration 18, no. 1-2 (2011): 365–75. http://dx.doi.org/10.1155/2011/284103.
Повний текст джерелаАнотація:
In this paper, we investigate the joint viscous friction effects on the motions of a two-bar linkage under controlling of OPCL. The dynamical model of the two-bar linkage with an OPCL controller is firstly set up with considering the two joints' viscous frictions. Thereafter, the motion bifurcations of the two-bar linkage along the values of joint viscous frictions are obtained using shooting method. Then, single-periodic, multiple-periodic, quasi-periodic and chaotic motions of link rotating angles are simulated with given different viscous friction values, and they are illustrated in time domain waveforms, phase space portraits, amplitude spectra and Poincare mapping graphs, respectively. Additionally, for the chaotic case, Lyapunov exponents and hypothesis possibilities of the two joint motions are also estimated.
5
Plainfossé, M., P. V. Hatton, A. Crawford, Z. M. Jin, and J. Fisher. "Influence of the extracellular matrix on the frictional properties of tissue-engineered cartilage." Biochemical Society Transactions 35, no. 4 (July 20, 2007): 677–79. http://dx.doi.org/10.1042/bst0350677.
Повний текст джерелаАнотація:
Low-friction surfaces are critical for efficient joint articulation. The tribological properties of articular cartilage have been studied extensively in native tissue and joints. Despite their importance, very few studies have examined the frictional properties of tissue-engineered cartilage. We have therefore reviewed the relationship between composition, structure and friction in tissue-engineered cartilage.
6
KIMURA, Masaaki, Kenji SEO, Masahiro KUSAKA, and Akiyoshi FUJI. "Relationship between friction time and joint strength of friction welding joints." Proceedings of Conference of Kansai Branch 2002.77 (2002): _9–57_—_9–58_. http://dx.doi.org/10.1299/jsmekansai.2002.77._9-57_.
Повний текст джерела
7
Lacki, P., W. Więckowski, and P. Wieczorek. "Assessment Of Joints Using Friction Stir Welding And Refill Friction Stir Spot Welding Methods." Archives of Metallurgy and Materials 60, no. 3 (September 1, 2015): 2297–306. http://dx.doi.org/10.1515/amm-2015-0377.
Повний текст джерелаАнотація:
Abstract FSW (Friction Stir Welding) and RFSSW (Refill Friction Stir Spot Welding) joints have been increasingly used in industrial practice. They successfully replace fusion-welded, riveted or resistance-welded joints. In the last two decades, dynamic development of this method has stimulated investigations of the fast methods for joint diagnostics. These methods should be non-destructive and easy to be used in technological processes. The methods of assessment of joint quality are expected to detect discontinuities in the structures welded using FSW and FSSW methods. Reliable detection of flaws would substantially extend the range of applications of FSW joints across many sectors of industry, including aviation. The investigations carried out in this paper allowed for characterization of defects present in FSW and RFSSW joints. Causes of these defects were also stressed. An overview of the methodologies for assessment of joint quality was presented. Results of assessment of the quality of joints made of 2024T6 aluminium sheet metal using FSW and RFSSW method were presented.
8
Yan, Xueyuan, Shen Shi, Xuhong Liu, and Huimin Mao. "Numerical Analysis of Mechanical Behavior of Self-Centering Joint between CFDST Column and RC Beam." Buildings 13, no. 1 (January 4, 2023): 135. http://dx.doi.org/10.3390/buildings13010135.
Повний текст джерелаАнотація:
The existing connection between the concrete-filled double steel tubular (CFDST) column and the reinforced concrete (RC) beam is difficult to repair and reuse after damage. In this paper, a self-centering joint between the CFDST column and the RC beam is proposed. The self-centering of the joint is realized by prestressed steel strands, and the energy dissipation is realized by friction. The overall purpose of the research is to analyze the influence of steel strand and friction on the mechanical behavior of the joint. By comparing the envelope curve and the restoring force model of a numerical joint model with theoretical values, accuracy of the numerical model was verified. Then, joints with different parameters, including the friction, prestress of steel strands, and ratio of the resisting moment provided by steel strands to the resisting moment provided by friction in the opening moment of joints, were numerically analyzed. The results showed that the joints with greater friction and prestress of steel strands had higher bearing capacity. Increasing the friction could increase the energy dissipation capacity of the joint, but it would increase the residual deformation of the joint. To reduce residual deformation, the prestress of steel strands should be increased. When the resultant force of the pretension of steel strands was greater than friction, the steel head could be kept pressed on the connecting block, making the stress changes of steel strands and the self-centering performance of the joint stable.
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Min, Gyeongjo, Daisuke Fukuda, Sewook Oh, Gyeonggyu Kim, Younghun Ko, Hongyuan Liu, Moonkyung Chung, and Sangho Cho. "Three-Dimensional Combined Finite-Discrete Element Modeling of Shear Fracture Process in Direct Shearing of Rough Concrete–Rock Joints." Applied Sciences 10, no. 22 (November 12, 2020): 8033. http://dx.doi.org/10.3390/app10228033.
Повний текст джерелаАнотація:
A three-dimensional combined finite-discrete element element method (FDEM), parallelized by a general-purpose graphic-processing-unit (GPGPU), was applied to identify the fracture process of rough concrete–rock joints under direct shearing. The development process of shear resistance under the complex interaction between the rough concrete–rock joint surfaces, i.e., asperity dilatation, sliding, and degradation, was numerically simulated in terms of various asperity roughness under constant normal confinement. It was found that joint roughness significantly affects the development of overall joint shear resistance. The main mechanism for the joint shear resistance was identified as asperity sliding in the case of smoother joint roughness and asperity degradation in the case of rougher joint asperity. Moreover, it was established that the bulk internal friction angle increased with asperity angle increments in the Mohr–Coulomb criterion, and these results follow Patton’s theoretical model. Finally, the friction coefficient in FDEM appears to be an important parameter for simulating the direct shear test because the friction coefficient affects the bulk shear strength as well as the bulk internal friction angle. In addition, the friction coefficient of the rock–concrete joints contributes to the variation of the internal friction angle at the smooth joint than the rough joint.
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Vagts, Steffen, Josef Schlattmann, Alexander Kovalev, and Stanislav N. Gorb. "Structure and Frictional Properties of the Leg Joint of the Beetle Pachnoda marginata (Scarabaeidae, Cetoniinae) as an Inspiration for Technical Joints." Biomimetics 5, no. 2 (April 20, 2020): 14. http://dx.doi.org/10.3390/biomimetics5020014.
Повний текст джерелаАнотація:
The efficient locomotion of insects is not only inspiring for control algorithms but also promises innovations for the reduction of friction in joints. After previous analysis of the leg kinematics and the topological characterization of the contacting joint surfaces in the beetle Pachnoda marginata, in the present paper, we report on the measurement of the coefficient of friction within the leg joints exhibiting an anisotropic frictional behavior in different sliding directions. In addition, the simulation of the mechanical behavior of a single microstructural element helped us to understand the interactions between the contact parts of this tribological system. These findings were partly transferred to a technical contact pair which is typical for such an application as joint connectors in the automotive field. This innovation helped to reduce the coefficient of friction under dry sliding conditions up to 17%.
11
Kato, Masayoshi, and Hiroshi Ota. "Lateral Excitation of a Rotating Shaft Driven by a Universal Joint With Friction." Journal of Vibration and Acoustics 112, no. 3 (July 1, 1990): 298–303. http://dx.doi.org/10.1115/1.2930508.
Повний текст джерелаАнотація:
The relative angular motion between a cross-pin and yokes of a universal joint gives rise to viscous and Coulomb’s frictions. A driven rotating shaft resultingly undergoes a moment caused by these frictions. This moment about a joint center has a component perpendicular to the driven shaft, and might be responsible for introducing lateral vibrations of the driven shaft. Analysis of these excitation components, supplemented with experimental results, confirms that excitations due to viscous friction enlarge with an increase in the joint angle, but are extremely small in practice, and that the excitations due to Coulomb’s friction are independent of the joint angle.
12
Skowrońska, Beata, Tomasz Chmielewski, and Dariusz Zasada. "Assessment of Selected Structural Properties of High-Speed Friction Welded Joints Made of Unalloyed Structural Steel." Materials 16, no. 1 (December 22, 2022): 93. http://dx.doi.org/10.3390/ma16010093.
Повний текст джерелаАнотація:
Commonly used S235JR structural steel, generally associated with good weldability, was joined by high-speed friction welding (HSFW). The friction welding tests were performed with a rotational speed of n = 8000 rpm and four different values of the unit pressure in the friction phase (pf) in the range of 64–255 MPa. The obtained joints were subjected to metallographic observations using an optical microscope; in selected zones of friction joints the average grain size was specified in accordance with the EN ISO 643:2012 standard; the hardness of friction joints was measured using the Vickers method. The friction-welded joint with the highest pf was EBSD-investigated. The obtained friction-welded joints resembled an hourglass, and the microstructure of individual zones of the joints differed depending on the height (axis, radius) of the observations. The generated joining conditions resulted in a significant refinement of the microstructure in the friction weld—the average grain size is about 1 µm2 (for base material it was 21 µm2). The highest increase in hardness above 340 HV0.1 was recorded in the friction weld of the welded joint with the lowest used value pressure in the friction phase. Such a sharp increase in hardness can make the resulting friction-welded joint become sensitive to dynamic or fatigue loads. The electron backscatter diffraction (EBSD) investigation confirmed the strong refinement of the microstructure in the friction-welded joint and the occurrence of the phenomenon of dynamic recrystallization (DRX). The friction weld was also characterized by a large share of high-angle boundaries (HAGBs) >80%. These results may indicate that during high-speed friction welding it is possible to create conditions like those obtained during the High-Pressure Torsion (the method used to produce UFG materials) process.
13
Askari, Ehsan, and Michael S. Andersen. "On the Effect of Friction on Tibiofemoral Joint Kinematics." Applied Sciences 11, no. 16 (August 16, 2021): 7516. http://dx.doi.org/10.3390/app11167516.
Повний текст джерелаАнотація:
The effect of friction on nonlinear dynamics and vibration of total knee arthroplasties is yet to be investigated and understood. This research work aims at studying the influence of friction on nonlinear dynamics, friction-induced vibration, and damage of tibiofemoral joints. For this purpose, a spatial dynamic knee model is developed using an asymmetric nonlinear elastic model accounting for knee joint ligaments and a penalty contact model to compute normal contact stresses in the joint while contact detection is treated such that the associated computational time is reduced. Several friction models are considered and embedded in the dynamic model to estimate tangential friction forces in the knee joint. External loads and moments, due to the presence of all soft tissues, e.g., muscles and hip-joint reaction forces, applied to the femoral bone are determined using a musculoskeletal approach. In the post-processing stage, damage, i.e., wear and creep, are estimated using three wear models and an empirical creep formulation, respectively. In addition, a FFT analysis is performed to evaluate likely friction-induced vibration of tibiofemoral joints. Mesh density analysis is performed and the methodology is assessed against outcomes available in the literature. It can be concluded that friction influences not only the tribology, but also dynamics of the knee joint, and friction-induced vibration is likely to take place when the friction coefficient increases.
14
Rajendran, Chinnasamy, Kasi Srinivasan, Visvalingam Balasubramanian, Tushar Sonar, and Haridasu Balaji. "Friction stir welding for manufacturing of a light weight combat aircraft structure." Materials Testing 64, no. 12 (November 29, 2022): 1782–95. http://dx.doi.org/10.1515/mt-2022-0165.
Повний текст джерелаАнотація:
Abstract This paper aims to validate the viability of friction stir welding process (FSW) to join high strength aerospace grade AA2014-T6 aluminium alloy for manufacturing light-weight combat aircraft (LCA) structure as a replacement to riveting process. FSW is used to overcome the heat input-related problems in fusion welding of AA2014-T6 aluminium alloy such as coarse grain fusion zone microstructure, softening in HAZ and lower joint efficiency. The 2 mm thick AA2014-T6 aluminium alloy sheets were used as the base material (BM). Friction stir butt (FBW) and friction stir lap (FLP) joints were developed, and its performance was compared with double cover riveted butt (DRB) joint in butt (RBJ) and lap (RLJ) joint configuration. Results showed that the load-carrying capability of FSW joints is greater than the riveted joints. The superior load-carrying capacities of FBW and FLW joints refers to evolution of refined grains and strengthening precipitates in stirred zone (SZ), which ensures superior metallurgical bonding between the joining surfaces. The riveted joints disclosed inferior load-carrying capacities due to the lack of metallurgical connection between the joining surfaces.
15
Ceschini, Lorella, Alessandro Morri, and Fabio Rotundo. "Friction Welding of Particle Reinforced Aluminium Based Composites." Materials Science Forum 678 (February 2011): 85–93. http://dx.doi.org/10.4028/www.scientific.net/msf.678.85.
Повний текст джерелаАнотація:
The widespread use of metal matrix composites (MMC) is often limited due to the difficulties related to their joining by means of traditional fusion welding processes. The aim of this work was to evaluate the effect on microstructure and mechanical properties (hardness and tensile strength) of two different friction welding techniques used for joining two Al-based metal matrix composites. In particular, Friction Stir Welding was applied to a 6061 (Al-Mg-Si) alloy matrix, reinforced with 20vol.% of Al2O3particles (W6A20A), while Linear Friction Welding was applied to a 2124 (Al-Cu-Mg) alloy matrix reinforced with 25vol.% of SiC particles (AMC225xe). Both the welding processes permitted to obtain substantially defect-free joints, whose microstructures was found to be dependent on both the initial microstructure of the composites and the welding processes. Hardness decrease was in the order of 40% for the FSW joint and of 10% for the LFW joint, mainly due to overaging of the matrix induced by the frictional heating, while the joint efficiency in respect to the ultimate tensile strength was 72% and 82%, respectively. Elongation to failure increased in the FSW joint due to coarsening of precipitates, whereas it decreased in the LFW joints due to the fibrosity in the thermomechanically altered zone. Fracture surface analysis showed good matrix/reinforcement interface for both composites.
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Dursun, Tolga, and Costas Soutis. "A finite element analysis of bolted joints loaded in tension: protruding head and countersunk fastener." International Journal of Structural Integrity 8, no. 1 (February 6, 2017): 35–50. http://dx.doi.org/10.1108/ijsi-09-2015-0033.
Повний текст джерелаАнотація:
Purpose The purpose of this paper is to investigate the effect of fastener geometry (protruding head and countersunk fastener) and friction coefficient on the stress distributions around the hole of the double-lap single bolted aluminium alloy joints. Design/methodology/approach 3D finite element analyses of double-lap bolted 7075-T6 aluminium joints were carried out. An elastic-plastic multi-linear kinematic hardening material behaviour was assumed for the Al alloy. Contact was defined using an augmented-Langrange contact algorithm, including the friction effect. Bolt clamping force and remote axial tensile loading were applied in two load steps and their separate and combined effects on the joint behaviour were investigated for two types of fastener configurations. Findings It was observed that bolt clamping reduces the axial tensile stress at the hole edge by introducing a through-thickness compressive stress. This reduction in stress concentration may have a beneficial effect on the fatigue life of the joint. Second, bolt clamping reduces the bearing stress at the fastener hole by creating a frictional force between the joint plates. Results showed that the joint with protruding head fastener shows lower tensile stress concentration, and lower bearing stress, near the bolt hole of the middle plate. Originality/value Bolt clamping force reduces both the stress concentration near the hole edge and the bearing stress at the hole by creating a frictional force. Joint with a protruding head fastener may lead to higher load carrying capability and improved fatigue life. Friction coefficient affects the stress levels around the bolt hole.
17
Xu, Fan, Fang, Wang, Zhu, and Zhao. "A Novel Virtual Sensor for Estimating Robot Joint Total Friction Based on Total Momentum." Applied Sciences 9, no. 16 (August 14, 2019): 3344. http://dx.doi.org/10.3390/app9163344.
Повний текст джерелаАнотація:
Robot joint friction is an important and complicated issue in improving robot control performance. In this paper, a virtual sensor based on the total generalized momentum concept is proposed to estimate the total friction torque, including both the motor-side and link-side friction, of robot joints without joint torque sensors. The proposed algorithm only requires a robot joint dynamics model and not a complex friction model dependent on factors such as time and velocity. By compensating for the estimated friction torque with a robot joint controller, the trajectory tracking performance of the controller, especially the velocity tracking performance, can be improved. To verify the effectiveness of the developed algorithm, 2-DOF planar manipulator simulations and single-joint system experiments are conducted. The simulation and experimental results show that the designed virtual sensor can effectively estimate the total joint friction disturbance and that the controller trajectory tracking performance is improved after observed friction compensation. However, the position tracking performance improvement of the controller is less than that for the velocity tracking performance improvement during the experiments. In addition, the velocity step response ability and velocity tracking performance of the controller are improved more at low velocities than that at high velocities in the experiments. The proposed algorithm has engineering and theoretical significance for estimating robot joint friction and improving the performance of robot joint controllers.
18
Gaul, L., and R. Nitsche. "The Role of Friction in Mechanical Joints." Applied Mechanics Reviews 54, no. 2 (March 1, 2001): 93–106. http://dx.doi.org/10.1115/1.3097294.
Повний текст джерелаАнотація:
Vibration properties of most assembled mechanical systems depend on frictional damping in joints. The nonlinear transfer behavior of the frictional interfaces often provides the dominant damping mechanism in a built-up structure and plays an important role in the vibratory response of the structure. For improving the performance of systems, many studies have been carried out to predict, measure, and/or enhance the energy dissipation of friction. This article reviews approaches for describing the nonlinear transfer behavior of bolted joint connections. It gives an overview of modeling issues. The models include classical and practical engineering models. Constitutive and phenomenological friction models describing the nonlinear transfer behavior of joints are discussed. The models deal with the inherent nonlinearity of contact forces (eg, Hertzian contact), and the nonlinear relationship between friction and relative velocity in the friction interface. The research activities in this area are a combination of theoretical, numerical, and experimental investigations. Various solution techniques commonly applied to friction-damped systems are presented and discussed. Recent applications are outlined with regard to the use of joints as semi-active damping devices for vibration control. Several application areas for friction damped systems due to mechanical joints and connections like shells and beams with friction boundaries are presented. This review article includes 134 references.
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Dahlan, Hendery, Ahmad Kafrawi Nasution, Sulthan Asyraf Zuhdi, and Meifal Rusli. "Study of the Effect of Friction Time and Preheating on the Joint Mechanical Properties of Friction Welded SS 316-Pure Zn." Applied Sciences 13, no. 2 (January 11, 2023): 988. http://dx.doi.org/10.3390/app13020988.
Повний текст джерелаАнотація:
Friction Welding (FRW) is a solid-state welding method. This technology also permits the connecting of dissimilar and similar materials while consuming less electricity than conventional electric welding. Friction welding is frequently used to join a variety of components because it generates high-quality joints and is capable of joining a wide range of materials and their complexity. This research examined the friction welding of stainless steel and pure zinc. The investigation concentrated on the welding parameters, specifically the effect of friction time and provision of preheating on parameters with high joint strength, as well as the mechanical properties, microstructure, and characterization of the joint material. The results of the experimental research indicated that the welding settings had a significant impact on the friction welding process. The tensile strength increased as a result of the reduced friction duration during the welding process, as demonstrated by the experimental findings. The longer the friction period, the more an oxide layer will form on the surface of the metal, preventing the diffusion process and impacting the production of the intermetallic phase for the joint’s strength.
20
Chen, Yu, Huaying Li, Xiaoyu Wang, Hua Ding, and Fenghe Zhang. "A Comparative Investigation on Conventional and Stationary Shoulder Friction Stir Welding of Al-7075 Butt-Lap Structure." Metals 9, no. 12 (November 26, 2019): 1264. http://dx.doi.org/10.3390/met9121264.
Повний текст джерелаАнотація:
Both conventional friction stir welding (C-FSW) and stationary shoulder friction stir welding (S-FSW) were employed to join the Al-7075 butt-lap structure, then the microstructural evolution and mechanical characterization of all FSW joints were systematically studied. The C-FSW joint exhibited a rough surface with flashes and arc corrugations, while the surface of the S-FSW joint became smooth. Moreover, for the S-FSW joint, the shoulder-affected zone got eliminated and the material flow mode during FSW was changed owning to the application of stationary shoulder. Furthermore, in comparison to C-FSW, the lower welding heat input of S-FSW decreased the average grain size in the nugget zone and inhibited the coarsening of strengthening precipitates in the heat-affected zone, elevating the overall hardness for the S-FSW joint. In addition, the tensile strength of the S-FSW joint became higher compared to the C-FSW joint, and all the FSW joints failed inside the nugget zone attributing to the existence of hook defect. The sharp-angled hook defect deteriorated the plasticity of the C-FSW joint further, which was only 70% that of the S-FSW joint.
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KUMAR, Shailendra, Shikhar SHUKLA, and Krishna KANT SHUKLA. "Rotational wood welding of Dalbergia sissoo wood: forming longitudinal tongue-and-groove and butt joints." BOIS & FORETS DES TROPIQUES 347 (March 25, 2021): 5–11. http://dx.doi.org/10.19182/bft2021.347.a31865.
Повний текст джерелаАнотація:
Wood joinery is an essential part of woodworking for product manufacture. Wood sections are mostly joined together with adhesives. Wood welding brings a new dimension to joinery by using mechanical friction to induce a flow of wood components ensuring adhesion. In this study, a customized spin wood-welding machine was used to join wood sections of Dalbergia sissoo. Butt and tongue-and-groove joints were prepared and welded using the machine. The tensile strength of the joints was tested. The impact on joint strength of increasing the friction area by introducing tongue-and-groove joints was tested and analyzed. The tensile strength for butt joints at 1,200 rpm welding was estimated at 5.3 MPa. Joint strength was found to increase substantially (by 66%) with a tongue-and-groove welding section. Weld line temperatures at different spin times were also investigated. The aim of this study is to apply welding technology to Dalbergia sissoo to achieve greater joint strength.
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Febri Irwanto, Aris Widyo Nugroho, Totok Suwanda,. "Sifat Mekanis dan Struktur Mikro Pengelasan Gesek Baja Tahan Karat Austenitik AISI 304." Semesta Teknika 17, no. 1 (November 25, 2015): 83–90. http://dx.doi.org/10.18196/st.v17i1.413.
Повний текст джерелаАнотація:
The aim of this study is to investigate experimentally the microstructural properties and welding strengths of the friction welded joints using austenitic stainless steel (AISI 304) base metal. The experiments were carried out using a beforehand designed and constructed experimental friction welding set-up. Firstly, the welding experiments were under different friction pressure (1,38-4,14 MPa) and upsetting pressure (6,90-8,27 MPa). Later, the strengths of the joints were examined by tension test and the results were compared with those of the base metals. Microstructures in the interfaces of the joints were also obtained and examined. The results show that porosities were observed in bondline zone for all specimens. As the friction pressure increased, the fully plastically deformed zone becomes increased. Tensile test results indicated that, generally the joint strength is increased with an increase of the friction pressure and the upsetting pressure. The friction welded joint strenght were found to be lower than that of the base metal. The detailed fractographic observation confirmed that the brittle rupture occurred at the joint zone.
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Jun, Tea Sung, Shu Yan Zhang, Mina Golshan, Matthew J. Peel, David G. Richards, and Alexander M. Korsunsky. "Synchrotron Energy-Dispersive X-Ray Diffraction Analysis of Residual Strains around Friction Welds between Dissimilar Aluminium and Nickel Alloys." Materials Science Forum 571-572 (March 2008): 407–12. http://dx.doi.org/10.4028/www.scientific.net/msf.571-572.407.
Повний текст джерелаАнотація:
Friction welding processes, such as friction stir welding (FSW) and inertia friction welding (IFW) are popular candidate procedures for joining engineering materials (including dissimilar pairs) for advanced applications. The advantages of friction welding include lack of large scale material melting, ability to join dissimilar materials, and relatively low propensity to introduce defects into the weld joint. For these reasons FSW and IFW have become the subjects of a number of studies aimed at optimising the joining operations to obtain improved joint strength and reduce distortion and residual stress. In the present study we used the diffraction of high energy polychromatic synchrotron X-rays to measure interplanar lattice spacings and deduce nominal elastic strains in friction stir welds between dissimilar aluminium alloys AA5083 and AA6082, and in coupons from inertia friction welds between dissimilar nickel-base superalloys IN718 and RR1000. Energy-dispersive diffraction profiles were collected by two detectors mounted in the horizontal and vertical diffraction planes, providing information about lattice strains in two nearly perpendicular directions lying almost in the plane of the plate samples mounted perpendicularly to the incident beam. Two-dimensional maps of residual stresses in friction-welded joints were constructed. Apart from the 2D mapping technique, the sin2ψ method (transmission) was also used in the case of inertia friction-welded joint between nickel alloys. Comparison between the two results allowed the variation of the lattice parameter with the distance from the bond line to be deduced. It was found that friction welding of two dissimilar materials with significant strength mismatch may lead to the creation of a region of compressive stress in the vicinity of the bond line, in contrast with the behaviour observed for joints between similar materials.
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Wei, Yanni, and Fu Sun. "Microstructures and Mechanical Properties of Al/Fe and Cu/Fe Joints by Continuous Drive Friction Welding." Advances in Materials Science and Engineering 2018 (June 27, 2018): 1–8. http://dx.doi.org/10.1155/2018/2809356.
Повний текст джерелаАнотація:
The dissimilar pure metals Al/Fe and Cu/Fe with different metallurgical compatibility were joined by continuous drive friction welding. The friction weldability was investigated. The microstructure of the joining interface was analyzed by scanning electron microscopy, and the chemical compositions were tested by energy-dispersive spectroscopy. The joining strength was evaluated by tensile test, and the fracture was detected by X-ray diffraction analysis. The results show that sound joints of Al/Fe and Cu/Fe can be obtained by continuous drive friction welding process. A discontinuous reaction layer was formed on Al/Fe interface, and no obvious reaction layer appeared on Cu/Fe interface. The tensile strength of the joints increased with increasing friction pressure, and the highest strength could reach up to 70 MPa for Al/Fe joint and 222 MPa for Cu/Fe joint. All the Al/Fe friction-welded samples failed at the friction interface, while the Cu/Fe joint under 36 and 44 MPa friction pressure failed at Cu matrix during the tensile test.
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Gao, Liming, Jianjun Yuan, and Yingjie Qian. "Torque control based direct teaching for industrial robot considering temperature-load effects on joint friction." Industrial Robot: the international journal of robotics research and application 46, no. 5 (August 19, 2019): 699–710. http://dx.doi.org/10.1108/ir-12-2018-0254.
Повний текст джерелаАнотація:
Purpose The purpose of this paper is to design a practical direct teaching method for the industrial robot with large friction resistance and gravity torque but without expensive force/torque sensor, where the gravity torque is just a function of joints position, whereas the friction is closely associated with joint velocity, temperature and load. Design/methodology/approach In the teaching method, the output torque of joint motor is controlled through current to compensate gravity torque completely and friction resistance incompletely. Three variables closely associated with friction are investigated separately by experiment and theoretical analysis, and then a comprehensive friction model which is used to calculate the required compensated friction torque is proposed. Finally, a SIASUN 7 degrees of freedom robot was used to verify the model and the method. Findings Experimental results demonstrated that the teaching method enables an operator to teach the robot in joint space by applying small force and torque on either end-effector or its body. The friction investigation suggests that the velocity and temperature have a strong nonlinear influence on viscous friction, whereas load torque significantly influences the Coulomb friction linearly and causes a slight Stribeck effect. Originality/value The main contribution includes the following: a practical joint space direct teaching method for a common industrial robot is developed, and a friction model capturing velocity, temperature and load for robot joints equipped with commercialized motors and harmonic drives is proposed.
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Li, Bingqi, Zhenyu Zhang, Xiaogang Wang, and Xiaonan Liu. "Investigation on cohesive zone model of bolted joint for water conveyance tunnel lining." Engineering Computations 36, no. 5 (June 10, 2019): 1449–68. http://dx.doi.org/10.1108/ec-07-2018-0310.
Повний текст джерелаАнотація:
Purpose The behavior of joints has a significant effect on the stability of water conveyance tunnel. The purpose of this paper is to study the contact and friction at the joint of the tunneling segment lining and establish its contact friction model. At the same time, the stress and deformation characteristics at the joint of the segment under hydrostatic load are analyzed. Design/methodology/approach In this study, the contact and friction in a bolted joint are examined using shear testing. The feasibility of the proposed model is verified by a numerical simulation of tests and a theoretical analysis. Accordingly, the effect of joints on the lining is explored under internal hydrostatic loading. Findings The results show that the openings of tunnel segments in joints gradually expand from the positions of the inner and outer edges to the location of the bolt. Moreover, the stress concentration zone is formed at the bolt. Under hydraulic loading, the opening displacement at the joint increases as the water pressure increases; nevertheless, it does not exceed engineering requirements. When the water pressure of the tunnel lining joint reaches 0.5 MPa, the opening of the joint slowly increases. When the water pressure exceeds 0.7 MPa, the opening of the joint rapidly and significantly increases. Originality/value Contact and friction in a bolted joint were examined using shear testing. A cohesive zone model of bolted joints was proposed based on test results. The influence of joint behavior on the stability of water conveyance tunnel was studied.
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Ravendra, Jujavarapu Sai, and Palukuri Veerendra. "Studies on Effect of Tool Pin Profiles and Welding Parameters on the Friction Stir Welding of Dissimilar Aluminium Alloys AA5052 & AA6063." International Journal for Research in Applied Science and Engineering Technology 10, no. 4 (April 30, 2022): 3077–89. http://dx.doi.org/10.22214/ijraset.2022.41986.
Повний текст джерелаАнотація:
Abstract: Friction stir welding (FSW) is a solid-state joining process that uses the frictional heat generated by the rotating tool to soften the metals to form the joint. It is an effective technique for joining dissimilar aluminum alloys and finds its application in various fields such as aerospace and automotive industries. FSW process is energy efficient and environment friendly process. This FSW can produce joints with higher mechanical and metallurgical properties. Formerly, FSW was adopted for low melting metals like aluminum alloys. The various FSW parameters play a vital role in determining the quality of the welded joint. The parameters included in the study of different tool pin profiles (circular, pentagon and taper). FEA analysis will be performed for friction stir welding of Aluminum alloy 5052 and AA6063 at different tool pin profiles using ANSYS. This paper mainly focuses on studying the effect of different tool pin profiles on the microstructure and mechanical properties of the dissimilar AA5052 and AA6063 aluminum alloy joints. The weld quality characteristics like microstructure, micro-hardness, and tensile properties of the joints are analyzed and presented for three different tool pin profiles. It is observed from the result that the joint fabricated using three different tool pin profiles exhibits the better mechanical properties when compared to other joints. Index Terms: Friction stir welding, Aluminium alloys, AA5052, AA6063, Dissimilar welding.
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Muribwathoho, Oritonda, Velaphi Msomi, Ali Merdji, and Sipokazi Mabuwa. "The effect of material position of multi-pass friction stir processing on friction stir welded AA1050/AA6082 dissimilar joints." E3S Web of Conferences 309 (2021): 01001. http://dx.doi.org/10.1051/e3sconf/202130901001.
Повний текст джерелаАнотація:
The AA1050 and AA6082 plates were used in producing dissimilar joint through friction stir welding (FSW) technique. The developed dissimilar joint was then subjected to multi-pass friction stir processing (FSP) technique. Various tests for the AA1050/AA6082 (AA1050 on the advancing side) and AA6082/AA1050 (AA6082 on the advancing side) joints were conducted on joints subjected to 1pass (1P) and 4pass (4P). The microstructural analysis showed that the increase in number of FSP passes resulted in a reduced grain size regardless of the of material position. The Vickers microhardness for AA1050/AA6082 FSPed joints increased towards AA6082 side while the microhardness for AA6082/AA1050 FSPed joints decreased towards the AA 1050 side regardless the number of the passes. The ultimate tensile strength (UTS) of AA1050/AA6082 joint increased with an increase in the number of passes while AA6082/AA1050 fluctuated between the specimens sampled from different locations of the FSPed joints.
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Liu, Zhenlei, Kang Yang, and Dejun Yan. "Refill Friction Stir Spot Welding of Dissimilar 6061/7075 Aluminum Alloy." High Temperature Materials and Processes 38, no. 2019 (February 25, 2019): 69–75. http://dx.doi.org/10.1515/htmp-2017-0139.
Повний текст джерелаАнотація:
AbstractRefill friction stir spot welding (RFSSW) was used to join 6061-T6 and 7075-T6 aluminum alloys in this work. Different sheet configurations and welding parameters were used to optimize joint strength. The effect of sleeve plunge depth on the microstructure and mechanical properties of the joints were investigated. The results showed that no defects were obtained when 6061-T6 aluminum alloy was placed as the upper sheet. The lap shear failure load of the joint using 6061-T6 aluminum alloy as the upper sheet was higher than that using 7075-T6 as the upper sheet. The maximum failure load of 12,892 N was attained when using the sleeve plunge depth of 3.6 mm. The joint failed at the upward flowing 7075 near the hook.
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Wang, Gaoxin, and Youliang Ding. "The Interface Friction in The Friction-Type Bolted Joint of Steel Truss Bridge: Case Study." Baltic Journal of Road and Bridge Engineering 15, no. 1 (March 17, 2020): 187–210. http://dx.doi.org/10.7250/bjrbe.2020-15.467.
Повний текст джерелаАнотація:
The friction-type bolted joint transfers the internal forces in the structural members by interface friction, but noticeable seasonal temperature and bolt fracture cause the redistribution of interface friction and threaten the joint safety. Therefore, this study carried out finite element analysis on the interface friction considering the influence of seasonal temperature and bolt fracture. Through finite element analysis, the simulation of interface friction under seasonal temperature revealed the distribution of temperature induced interface friction in different areas and locations. Further simulation of fractured bolts revealed the influence of quantity and location of fractured bolts on the redistribution of interface friction. Finally, the interface frictions in the bolted joint were evaluated using limit state equations. The results showed that: 1) the quantity and location of fractured bolts cause obvious redistribution of interface friction in the bolt-fractured areas; 2) the quantity and location of fractured bolts have slight effect on the total interface friction in the whole splice plate; 3) the reduced interface friction in the bolt-fractured areas was transferred to the areas without bolt fracture, producing little change in the total interface friction; 4) all the splice plates had abundant safety margin after analysis of their limit state equations.
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Dien, Nguyen Phong, and Nguyen Van Khang. "Dynamic force analysis of a six-link planar mechanism under consideration of friction at the joints." Vietnam Journal of Mechanics 26, no. 2 (July 1, 2004): 65–75. http://dx.doi.org/10.15625/0866-7136/26/2/5690.
Повний текст джерелаАнотація:
The dynamic analysis of mechanisms with joints friction is complex since the frictional force depends nonlinearly on the resultant reactive force between the two mating surfaces of the joint. In this paper a non-iterative approximate method is used for determining the joint reaction forces and the driving torque of mechanisms is considered. By using the computing program MATLAB the dynamic forces of a six-link planar mechanism are calculated with this method.
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Chen, Shibiao, Gang Cheng, and Yusong Pang. "Dynamic Analysis and Trajectory Tracking Control for a Parallel Manipulator with Joint Friction." Applied Sciences 12, no. 13 (July 1, 2022): 6682. http://dx.doi.org/10.3390/app12136682.
Повний текст джерелаАнотація:
To overcome the bearing capacity deficiencies of traditional serial hip joint simulators, complex trajectory simulation, among others, as well as a parallel manipulator with two pairs of artificial hip joints and two moving platforms are proposed. The movements and driving forces of the parallel manipulator under the required motion and loading are studied to provide a basis for further research. In this study, the modeling and analysis of inverse kinematics and dynamics for a parallel manipulator with joint friction are derived. In the inverse kinematic model, kinematic relationships between the linear module slider and the moving platform are established, and expressions for the slider are deduced. Subsequently, by analyzing the frictional forces of the artificial hip joint and thrust ball bearing, a rigid body dynamics model of the parallel manipulator with joint friction is established, which is subsequently decomposed into four driving torques associated with the moving platform, joint lever, slider, and screw. Finally, the difference in the kinematic performance between the two moving platforms is analyzed using numerical simulations and experiments, and the accuracy of the established model is verified.
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Oh, Jun Kyun, Cengiz Yegin, and Mustafa Akbulut. "Micro/Nanoscale Tribological and Mechanical Investigation of the Articular Surfaces of Katydid Leg Joints: Potential for the Novel Bioinspired Lubrication Systems." MRS Advances 2, no. 19-20 (2017): 1117–23. http://dx.doi.org/10.1557/adv.2017.81.
Повний текст джерелаАнотація:
ABSTRACTInsects are recognized with their ability to efficiently move, operate, and function, and hence are inspiration for the design of micromechanical systems. This work deals with the structural, mechanical, and frictional characterization of the leg joint articulations of the katydid (Orthoptera: Tettigoniidae). For the katydids, the tibia joints were found to show a nanosmooth texture while the femur joint had a micro/nanotextured surface characteristics. The nanotexture was a two-tone periodic patterns with the hierarchical structures involving cylindrical ridges that are covered with nanoscale lamellar patterns perpendicular to the long axis and valleys between ridges that are decorated with the hillock patterns. The tibia and femur contact regions showed the reduced elastic modulus (Er) values ranging from 0.88 ± 0.01 GPa to 3.90 ± 0.11 GPa. The friction coefficient (μ) value of 0.053 ± 0.001 was recorded for the sliding contact of the tibia joint against the femur joint in air under dry conditions. The low friction values are attributed to the reduced real area of contact between the joint pair due to the coupling of the nanosmooth surfaces against the hierarchically nanotextured surfaces.
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Eyvazian, Arameh, Abdel Magid Hamouda, Hamed Aghajani Derazkola, and Majid Elyasi. "Study on the effects of tool tile angle, offset and plunge depth on friction stir welding of poly(methyl methacrylate) T-joint." Proceedings of the Institution of Mechanical Engineers, Part B: Journal of Engineering Manufacture 234, no. 4 (November 29, 2019): 773–87. http://dx.doi.org/10.1177/0954405419889180.
Повний текст джерелаАнотація:
The effects of tilt angle (TTA), plunge depth (TPD) and offset (TO) of tool in friction stir welding of poly(methyl methacrylate) T-joint were investigated. To understand better the effects of process parameter, thermomechanical simulation of joint was assessed. The results seem to show that at higher TPD and TTA, frictional heat increases. Woven tissue structure joint line forms after friction stir welding of poly(methyl methacrylate) sheets. The distance of woven layers was affected by TPD and TTA, while TO do not significantly affect heat generation of joint. The best material flow and adequate heat are generated at 0 mm TA, 2° TTA and 0.2 mm TPD, respectively. The highest flexural and tensile strength of friction stir welded joint were approximately 93% and 90% of as-received poly(methyl methacrylate), respectively. Crack forking was detected on the fractured surface of flexural samples and crack path was detected in the vicinity of shrinkage holes at fracture surface of tensile samples. These holes and degradation of poly(methyl methacrylate) during friction stir welding process decrease strength and hardness of the joint.
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Mańkowska-Snopczyńska, Anita, Witold Piekoszewski, Marian Szczerek, Waldemar Tuszyński, Ireneusz Kotela, and Andrzej Kotela. "METHODOLOGY FOR TESTING A JOINT CARTILAGE." Tribologia 294, no. 6 (April 12, 2021): 29–38. http://dx.doi.org/10.5604/01.3001.0014.8333.
Повний текст джерелаАнотація:
A research method was developed to analyse the tribological properties of cartilage tissue. Based on the literature data and the possibility of obtaining samples of appropriate dimensions, the frequency and amplitude of friction tests were adopted. Based on the previously conducted preliminary tests, other test parameters were proposed, such as the frictional contact load and the number of test runs. It was assumed that the results of the research will be the friction coefficient and the wear intensity of the tribological system. According to the developed method, a series of verification tests was carried out in which the friction contact was lubricated in various ways with the selected lubricants. The results of tests of animal cartilage in nonlubricated contact were used as the reference basis for all the tested associations. The friction tests showed good method resolution and satisfactory repeatability. In the case of wear characteristics, a greater scatter of test results was observed. It is probably related to the varied geometrical structure of the cartilage surface as well as the elastic properties of the bone on which the tissue was placed. The correctness of the obtained results and a relatively good resolution of the tribological test method were found.
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Chapke, Yashwant, Dinesh Kamble, and Saoud Md Salim Shaikh. "Friction welding of Aluminium Alloy 6063 with copper." E3S Web of Conferences 170 (2020): 02004. http://dx.doi.org/10.1051/e3sconf/202017002004.
Повний текст джерелаАнотація:
Friction welding process is a forging welding process in which work piece are joined due to heat produced by friction between two joining surfaces and upset pressure is applied by non-rotating work piece. Joining of aluminum alloy with dissimilar material is important research area to focus on as maximum aircraft structures havexx Aluminum alloy frame and aerospace designers familiar with Aluminum alloy and its design considerations. After comparison of mechanical properties and application of light weight alloys aluminum alloys, tungsten, stainless steel and copper, copper selected as dissimilar material to join with Aluminum alloy AA6063. AA 6063 also known as architectural alloy selected based upon its properties. This dissimilar joint of AA6063 and Copper has application in electrical conductors as copper is good electrical conductivity and used in maximum electrical conductors. In this research work AA6063 joined with Copper successfully using Rotary Friction Welding process. Through process study effective process parameters like Friction Pressure, Upset Pressure, Spindle Speed, and Friction Time identified and their effect on weld joint strength were studied.Testing for measuring UTS of friction welded joint conducted. Using DOE tool optimized set process parameters for friction welding identified and their effect on weld joint strength studied experimentally. Maximum UTS of 222.787 MPa for Friction welded joint achieved, bend test also performed on friction welded samples.
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Ateshian, G. A., Huiqun Wang, and W. M. Lai. "The Role of Interstitial Fluid Pressurization and Surface Porosities on the Boundary Friction of Articular Cartilage." Journal of Tribology 120, no. 2 (April 1, 1998): 241–48. http://dx.doi.org/10.1115/1.2834416.
Повний текст джерелаАнотація:
Articular cartilage is the remarkable bearing material of diarthrodial joints. Experimental measurements of its friction coefficient under various configurations have demonstrated that it is load-dependent, velocity-dependent, and time-dependent, and it can vary from values as low as 0.002 to as high as 0.3 or greater. Yet, many studies have suggested that these frictional properties are not dependent upon the viscosity of synovial fluid. In this paper, a theoretical formulation of a boundary friction model for articular cartilage is described and verified directly against experimental results in the configuration of confined compression stress-relaxation. The mathematical formulation of the friction model can potentially explain many of the experimentally observed frictional responses in relation to the pressurization of the interstitial fluid inside cartilage during joint loading, and the equilibrium friction coefficient which prevails in the absence of such pressurization. In this proposed model, it is also hypothesized that surface porosities play a role in the regulation of the frictional response of cartilage. The good agreement between theoretical predictions and experimental results of this study provide support for the proposed boundary friction formulation.
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AVOUAC, JEROME, ULRICH WALKER, ALAN TYNDALL, ANDRÉ KAHAN, MARCO MATUCCI-CERINIC, and YANNICK ALLANORE. "Characteristics of Joint Involvement and Relationships with Systemic Inflammation in Systemic Sclerosis: Results from the EULAR Scleroderma Trial and Research Group (EUSTAR) Database." Journal of Rheumatology 37, no. 7 (June 15, 2010): 1488–501. http://dx.doi.org/10.3899/jrheum.091165.
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Objective.To determine the prevalence of and independent factors associated with joint involvement in a large population of patients with systemic sclerosis (SSc).Methods.This study was cross-sectional, based on data collected on patients included in the European League Against Rheumatism (EULAR) Scleroderma Trials and Research (EUSTAR) registry. We queried this database to extract data regarding global evaluation of patients with SSc and the presence of any clinical articular involvement: synovitis (tender and swollen joints), tendon friction rubs (rubbing sensation detected as the tendon was moved), and joint contracture (stiffness of the joints that decreased their range of motion). Overall joint involvement was defined by the occurrence of synovitis and/or joint contracture and/or tendon friction rubs.Results.We recruited 7286 patients with SSc; their mean age was 56 ± 14 years, disease duration 10 ± 9 years, and 4210 (58%) had a limited cutaneous disease subset. Frequencies of synovitis, tendon friction rubs, and joint contractures were 16%, 11%, and 31%, respectively. Synovitis, tendon friction rubs, and joint contracture were more prevalent in patients with the diffuse cutaneous subset and were associated together and with severe vascular, muscular, renal, and interstitial lung involvement. Moreover, synovitis had the highest strength of association with elevated acute-phase reactants taken as the dependent variable.Conclusion.Our results highlight the striking level of articular involvement in SSc, as evaluated by systematic examination in a large cohort of patients with SSc. Our data also show that synovitis, joint contracture, and tendon friction rubs are associated with a more severe disease and with systemic inflammation.
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Işık, Efe, and Çiçek Özes. "Determination of the Mechanical Properties of Friction Welded Tube Yoke and Tube Joint." Advances in Materials Science and Engineering 2016 (2016): 1–8. http://dx.doi.org/10.1155/2016/8918253.
Повний текст джерелаАнотація:
This paper deals with the friction welding of the tube yoke and the tube of the drive shaft used in light commercial vehicles. Tube yoke made from hot forged microalloyed steel and the tube made from cold drawn steel, with a ratio (thickness/outside diameter ratio) of less than 0.1, were successfully welded by friction welding method. Hardness distributions on both sides of the welded joint across the welding interface were determined and the microstructure of the joint was investigated. Furthermore, joint strength was tested under tensile, static torsional, and torsional fatigue loadings. The tested data were analyzed by Weibull distribution. The maximum hardness value along the welded joint was detected as 553 Hv1. The lowest detected tensile strength of the joint was 13% less than the base materials’ tensile strength. The torsional load carrying capacity of the friction welded thin walled tubular joint without any damage was obtained as 4.252,5 Nm in 95% confidence interval. After conducting fully reversed torsional fatigue tests, the fatigue life of friction welded tubular joints was detected as 220.066,3 cycles.
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Ali, Ghadanfer Hussein, and Sabah Khammass Hussein. "Friction spot lap joining of the anodized aluminium alloy 6061 with high-density polyethylene sheets." World Journal of Engineering 16, no. 4 (August 19, 2019): 539–49. http://dx.doi.org/10.1108/wje-12-2018-0415.
Повний текст джерелаАнотація:
Purpose The purpose of this paper is to join an anodized aluminium alloy AA6061 sheet with high-density polyethylene (HDPE) using friction spot process. Design/methodology/approach The surface of AA6061 sheet was anodized to increase the pores’ size. A lap joint configuration was used to join the AA6061 with HDPE sheets by the friction spot process. The joining process was carried out using a rotating tool of different diameters: 14, 16 and 18 mm. Three tool-plunging depths were used – 0.1, 0.2 and 0.3 mm – with three values of the processing time – 20, 30 and 40 s. The joining process parameters were designed according to the Taguchi approach. Two sets of samples were joined: the as-received AA6061/HDPE and the anodized AA6061/HDPE. Findings Frictional heat melted the HDPE layers near the lap joint line and penetrated it through the surface pores of the AA6061 sheet via the applied pressure of the tool. The tool diameter exhibited higher effect on the joint strength than processing time and the tool-plunging depth. Specimens of highest and lowest tensile force were failed by necking the polymer side and shearing the polymer layers at the lap joint, respectively. Molten HDPE was mechanically interlocked into the pores of the anodized surface of AA6061 with an interface line of 18-m width. Originality/value For the first time, HDPE was joined with the anodized AA6061 by the friction spot process. The joint strength reached an ideal efficiency of 100 per cent.
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KIMURA, Masaaki, Yosuke OHTSUKA, Gyu Beak AN, Masahiro KUSAKA, Kenji SEO, and Akiyoshi FUJI. "Joint strength of fine grained steel friction welded joints." Proceedings of the Materials and processing conference 2003.11 (2003): 329–30. http://dx.doi.org/10.1299/jsmemp.2003.11.329.
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Sobota, Piotr. "Determination of the Friction Work of a Link Chain Interworking with a Sprocket Drum / Wyznaczenie Pracy Tarcia Łańcucha Ogniwowego We Współdziałaniu Z Bębnem Łańcuchowym." Archives of Mining Sciences 58, no. 3 (September 1, 2013): 805–22. http://dx.doi.org/10.2478/amsc-2013-0056.
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Abstract The significant abrasive wear of sprocket drum teeth and seats bottoms is observed during the exploitation of longwall scraper conveyors. For this reason, it is important to determine friction work in sliding conditions of the horizontal link on the tooth seat bottom and on the tooth flank and friction work in the joint of links in the context of such nodes’ abrasive wear. The different construction variants of sprocket drums can be compared by determining friction work in the sliding positions of the horizontal link on the drum. The determination of the losses of the power transmitted is a requisite condition in such situation for determining the efficiency values of chain meshing. The friction work of the friction couple of a sprocket drum - link chain consists of friction work of the horizontal link in the places where it contacts with the seat bottom Ag and the tooth flank Af and friction work in the joints of a horizontal link in the contact place with vertical links: in the front joint Ap and the rear joint At. The article presents dependencies enabling to determine the value of such work for specific geometric relations between the chain and the drum and different friction conditions. The curves of relative friction work and the values of total friction work on the seat bottom, on the tooth flank and in a front and rear joint of links are presented for examples of friction conditions.
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Beards, C. F., and A. Woowat. "The Control of Frame Vibration by Friction Damping in Joints." Journal of Vibration and Acoustics 107, no. 1 (January 1, 1985): 26–32. http://dx.doi.org/10.1115/1.3274711.
Повний текст джерелаАнотація:
Some effects of friction damping occurring in joints on the frequency response of a portal frame are presented and discussed. The frame was designed so that the joint clamping forces could be varied, allowing some control of the friction damping caused by interfacial slip in the joints. It was found that a joint clamping force less than that required to tightly fasten a joint gave a minimum frame response: reducing the clamping force from 15 kN to 320 N caused a reduction in frame response of 21 dB. Some changes in resonance frequencies were also observed.
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Abolfazli, Milad, Milad Bazli, Hossein Heydari, and Ahmad Fahimifar. "Investigating the Effects of Cement and Polymer Grouting on the Shear Behavior of Rock Joints." Polymers 14, no. 6 (March 18, 2022): 1229. http://dx.doi.org/10.3390/polym14061229.
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This study carried out a comparison between cement grouting and chemical grouting, using epoxy and polyurethane, with respect to their effects on the shear behavior of joints. Joint replicas, with three different grades of surface roughness, were molded and grouted by means of cement and epoxy grouts of various mixtures. To investigate their shear behavior, samples were subjected to direct shear tests under constant normal load (CNL) condition. According to the results obtained, grouting improves the overall shear strength of the rock joints. All the grouted samples yielded higher maximum and residual shear strength in comparison with the non-grouted joint. Grouting resulted in an improvement in the cohesion of all the samples. However, a fall in friction angle by 5.26° in the sample with JRC of nine was observed, yet it was reduced by 2.36° and 3.26° for joints with JRC of 14 and 19, respectively. Cement grouts were found to have a more brittle behavior, whereas the chemical grouts were more ductile. Higher amounts of cement used in the grout mixture do not provide as much cohesion and only increase the brittleness of the grout. As a result of being more brittle, cement grout breaks into small pieces and joint planes are in better contact during shearing; consequently, there would be less of a fall in friction angle as opposed to epoxy grout whose ductile characteristic prevents grout chipping; therefore, joint planes are not in contact and a greater fall in the friction angle occurs. There was no noticeable change in the cohesion of the larger grouted joints. However, the friction angle of both natural and grouted joints increased in the larger joint. This can be related to the distribution of random peaks and valleys on the joint surface, which increases with the joint size.
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Hwang, Yong Ha, Keun Hyeok Yang, Jae Sung Mun, Hyun Sub Yoon, In Hyuk Hwang, and Hye Jin Lee. "Effect of Concrete Types and Construction Joints on Concrete Shear Friction Characteristics." Key Engineering Materials 723 (December 2016): 700–705. http://dx.doi.org/10.4028/www.scientific.net/kem.723.700.
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The present study examined the effect of smooth construction joint and concrete unit weight on the shear friction behavior of concrete. From nine push-off test specimens, shear load-relative slip relationships, shear cracking stress, shear friction strength were measured. Test results showed that the shear cracking stress was hardly affected by the configuration of transverse reinforcement or concrete unit weight. The shear friction strength of monolithic normal-weight concrete was approximately three times higher than that of the companion specimens with construction joint. Meanwhile, the heavyweight concrete joints had a similar shear friction strength to normal-weight concrete ones.
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Minasov, B. Sh, R. R. Yakupov, L. Sh Shuster, S. V. Chertovskikh, I. I. Emaev, G. N. Filimonov, A. A. Korshunov, and T. E. Khairov. "Comparative Study of the Adhesive Component of Friction in Hip Endoprostheses." Vestnik travmatologii i ortopedii imeni N.N. Priorova, no. 1 (March 30, 2016): 71–75. http://dx.doi.org/10.32414/0869-8678-2016-1-71-75.
Повний текст джерелаАнотація:
Kinematic unit friction pairs of human hip endoprosthesis and rabbit hips with induced osteoarthrosis were studied under conditions of either dry or biological medium friction. Deterioration of tribologic characteristics in destructive dystrophic lesions of joints is the key component of joint kinematic properties decompensation. Experimental animal model of osteoarthrosis showed negative influence of dystrophic changes upon the hip joint adhesive characteristics. Study of the adhesive component of friction coefficient in different tribologic pairs of endoprostheses detected that friction characteristics of the studied tribologic pairs depended upon the magnitude of external load and strength of the kinematic unit.
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Minasov, B. Sh, R. R. Yakupov, L. Sh Shuster, S. V. Chertovskikh, I. I. Emaev, G. N. Filimonov, A. A. Korshunov, and T. E. Khairov. "Comparative Study of the Adhesive Component of Friction in Hip Endoprostheses." N.N. Priorov Journal of Traumatology and Orthopedics 23, no. 1 (March 15, 2016): 71–75. http://dx.doi.org/10.17816/vto201623171-75.
Повний текст джерелаАнотація:
Kinematic unit friction pairs of human hip endoprosthesis and rabbit hips with induced osteoarthrosis were studied under conditions of either dry or biological medium friction. Deterioration of tribologic characteristics in destructive dystrophic lesions of joints is the key component of joint kinematic properties decompensation. Experimental animal model of osteoarthrosis showed negative influence of dystrophic changes upon the hip joint adhesive characteristics. Study of the adhesive component of friction coefficient in different tribologic pairs of endoprostheses detected that friction characteristics of the studied tribologic pairs depended upon the magnitude of external load and strength of the kinematic unit.
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Milčić, Miodrag, Dragan Milčić, Tomaž Vuherer, Ljubica Radović, Igor Radisavljević, and Aleksija Đurić. "Influence of Welding Speed on Fracture Toughness of Friction Stir Welded AA2024-T351 Joints." Materials 14, no. 6 (March 22, 2021): 1561. http://dx.doi.org/10.3390/ma14061561.
Повний текст джерелаАнотація:
In order to ensure a quality welded joint, and thus safe operation and high reliability of the welded part or structure achieved by friction stir welding, it is necessary to select the optimal welding parameters. The parameters of friction stir welding significantly affect the structure of the welded joint, and thus the mechanical properties of the welded joint. Investigation of the influence of friction stir welding parameters was performed on 6-mm thick plates of aluminum alloy AA2024 T351. The quality of the welded joint is predominantly influenced by the tool rotation speed n and the welding speed v. In this research, constant tool rotation speed was adopted n = 750 rpm, and the welding speed was varied (v = 73, 116 and 150 mm/min). By the visual method and radiographic examination, imperfections of the face and roots of the welded specimens were not found. This paper presents the performed experimental tests of the macro and microstructure of welded joints, followed by tests of micro hardness and fracture behavior of Friction Stir Welded AA2024-T351 joints. It can be concluded that the welding speed of v = 116 mm/min is favorable with regard to the fracture behavior of the analysed FSW-joint.
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Abdullah, Isam Tareq, Sabah Khammass Hussein, and Abbas Khammas Hussein. "Joining of aluminium alloy to pre-holed carbon steel by aluminium extrusion using friction spot method." International Journal of Structural Integrity 11, no. 6 (December 19, 2019): 849–60. http://dx.doi.org/10.1108/ijsi-10-2019-0112.
Повний текст джерелаАнотація:
Purpose The purpose of this paper is to join sheets of an aluminium alloy together with pre-holed carbon steel via friction spot technique. Design/methodology/approach An AISI 1006 steel sheet was a pre-holed with a 4.8 mm diameter and put under AA5052 sheet with a lap joint configuration. The joining process was carried out by extruding the aluminium through the steel hole using a rotating tool of 10 mm diameter. Furthermore, three process parameters (pre-heating time, rotating speed and plunging depth of the tool) with three values for each parameter were used to study their effects on the joints quality. In order to join samples, nine experiments were designed according to a Taguchi method. Shear strength, microstructure and X-ray diffraction tests of the joint were carried out. Findings The joining mechanism occurred by a mechanical interlock of the extruded aluminium with the inner surface of the steel hole. The tool plunging depth had a significant effect on the shear strength of the joint. The shear strength of two joints exceeded the shear strength of the wrought material (AA5052). All samples failed with two modes: pull-out and shearing of the extruded aluminium. Originality/value For the first time, the extrusion technique was used to join AA5052 sheet together with pre-holed carbon steel, with a perfect joint efficiency.
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Wang, Xi Jing, Chang Qing Zhang, Bo Qiang Li, and Tian Li. "A Preliminary Investigation on Friction Stir Spot Welding of Steel/Mg." Applied Mechanics and Materials 84-85 (August 2011): 529–33. http://dx.doi.org/10.4028/www.scientific.net/amm.84-85.529.
Повний текст джерелаАнотація:
Dissimilar metal of Steel and Magnesium alloy used for friction stir spot welding is studied. Based on using orthogonal test method optimizes the process parameters and gets satisfactory joints , SEM is used to observe the features of joint,XRD is applied to determine the joint phase, and the results show that: the design of rotating tool without pin is reasonable and it can form satisfactory joints without keyhole of spot welding. The performance of spot welding joint depends on the extent of diffusion of Zn and Mg and high weld consistency. There is small existence of intermetallics made of MgZn2,Mg0.97Zn0.03 in welding joint.The properties of joint depends on the intermetallics, Due to this,The microhardness of joint increases gradually from the magnesium side to steel side.