Journal articles: 'Fatigue of bearing alloys'

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Ali, M. S., P. A. S. Reed, S. Syngellakis, Andrew J. Moffat, and Carl Perrin. "Microstructural Factors Affecting Fatigue Initiation in Various Al Based Bearing Alloys." Materials Science Forum 519-521 (July 2006): 1071–76. http://dx.doi.org/10.4028/www.scientific.net/msf.519-521.1071.

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Microscale fatigue damage mechanisms in various Al-Sn-Si based bearing alloys used as linings of plain automotive bearings are reported. Extensive work on previously developed alloys has concluded that secondary phase particles such as Sn and Si are potential fatigue initiation sites with a complex combination of various particle geometry parameters. A newly developed alloy contains a number of complex widely scattered intermetallics with much finer and fewer Sn and Si particles. This alloy system appears to be more resistant to initiate microscale fatigue damage compared to the previous systems.

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Busby, A. K., and J. W. Martin. "Fatigue crack propagation in Al–Sn bearing alloys." Materials Science and Technology 5, no. 7 (July 1989): 689–98. http://dx.doi.org/10.1179/mst.1989.5.7.689.

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Syngellakis, S., M. S. Ali, and P. A. S. Reed. "Microstructural modelling of fatigue initiation in aluminium-bearing alloys." International Journal of Computational Methods and Experimental Measurements 1, no. 3 (May 16, 2013): 249–64. http://dx.doi.org/10.2495/cmem-v1-n3-249-264.

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Seyyedi, J. "Thermal Fatigue of Low-Temperature Solder Alloys in Insertion Mount Assembly." Journal of Electronic Packaging 115, no. 3 (September 1, 1993): 305–11. http://dx.doi.org/10.1115/1.2909333.

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Thermal fatigue resistance was investigated for insertion mount solder joints, manufactured with 58Bi-42Sn (wt. %), 43Sn-43Pb-14Bi, 52In-48Sn and 40In-40Sn-20Pb low-temperature alloys. Accelerated thermal cycling was used in conjunction with metallographic analysis to determine the fatigue resistance and to elucidate the failure mode for each solder composition. Additionally, the behavior of each solder alloy was compared to that of 63Sn-37Pb solder, tested under identical conditions. A two-phase microstructure with lamellar morphology was observed in 58Bi-42Sn, whereas a globular morphology was prevalent in the remaining alloys. The Bi-containing solders demonstrate fatigue resistance comparable to 63Sn-37Pb, but greater than the In-bearing alloys. These differences and microstructure changes prior to and during thermal fatigue testing are discussed.

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Della Corte, Christopher. "Novel Super-Elastic Materials for Advanced Bearing Applications." Advances in Science and Technology 89 (October 2014): 1–9. http://dx.doi.org/10.4028/www.scientific.net/ast.89.1.

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Tribological surfaces of mechanical components encounter harsh conditions in terrestrial, marine and aerospace environments. Brinell denting, abrasive wear and fatigue often lead to life-limiting bearing and gear failures. Novel superelastic materials based upon Nickel-Titanium (NiTi) alloys are an emerging solution. NiTi alloys are intermetallic materials that possess characteristics of both metals and ceramics. NiTi alloys have intrinsically good aqueous corrosion resistance (they cannot rust), high hardness, relatively low elastic modulus, are chemically inert and readily lubricated. NiTi alloys also belong to the family of superelastics and, despite high hardness, are able to withstand large strains without suffering permanent plastic deformation. In this paper, the use of a hard, resilient NiTi alloy for corrosion-proof, shockproof bearing and gear applications is presented. Through a series of bearing and gear development projects, it is demonstrated that NiTi’s unique blend of material properties lead to significantly improved load capacity, reduced weight and intrinsic corrosion resistance not found in any other bearing materials. NiTi thus represents a new materials solution to demanding tribological applications.

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Gawarkiewicz, Rafał, Jan Sikora, and Boguslaw Siwek. "Problems of Analytical Determination of Journal Bearing Bush Fatigue Strength Estimates." Key Engineering Materials 490 (September 2011): 247–56. http://dx.doi.org/10.4028/www.scientific.net/kem.490.247.

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Problems connected with determination of stress distribution in sliding layer of thin-walled bearing bushes, investigated in bearing fatigue test rigs, have been presented. Using an example of plain bearings tested in the fatigue machine SMOK (built at the Gdańsk University of Technology) problems with obtaining a convergence of iterative procedure for determining the fatigue strength estimators of bearing alloy surface layer are analyzed. Calculations consisting in successive iterations of pressure distribution in oil film and corresponding elastic deformation of the bearing bush and housing were based on finite-element method and utilized ANSYS program. The objective of calculation was the estimation of values of radial, tangential, axial and reduced stresses in surface layer of the bearing bush corresponding to experimentally determined load magnitudes leading to fatigue cracks initiation. The convergence of analytical procedure has been achieved by the use of a relaxation method.

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Mizobe, Koshiro, Edson Costa Santos, Takashi Honda, Hitonobu Koike, Katsuyuki Kida, and Takuya Shibukawa. "Effect of Repeated Quenching on the Rotating Bending Strength of SAE52100 Bearing Steel." Advanced Materials Research 457-458 (January 2012): 1025–31. http://dx.doi.org/10.4028/www.scientific.net/amr.457-458.1025.

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Martensitic high carbon high strength SAE 52100 bearing steel is one of the main alloys used for rolling contact applications where high wear resistance are required. Due to its high fatigue strength, SAE 52100 is recently being used not only for the production of bearings but also shafts. Refining of prior austenite grain through repeated quenching is a procedure that can be used to enhance the material’s strength. In this work, the microstructure of repeatedly quenched SAE 52100 steel and its fatigue strength under rotating bending were investigated. It was found that repeated furnace heating and quenching effectively refined the martensitic structure and increased the retained austenite content. Repeated quenching was found to improve the fatigue strength of SAE 52100.

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Watanabe, Chihiro, and Ryoichi Monzen. "Effects of Microstructures on Fatigue Behavior of an Al-Mg-Sc Alloy at an Elevated Temperature." Materials Science Forum 706-709 (January 2012): 426–30. http://dx.doi.org/10.4028/www.scientific.net/msf.706-709.426.

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Polycrystalline Al-1wt%Mg-0.27wt%Sc alloys bearing Al3Sc particles with different average sizes of 4 and 11nm in diameter have been cyclically deformed at 423K under various constant stress amplitudes, and the relationship between fatigue characteristics and microstructure of the alloy has been investigated. The specimen bearing 11 nm particles exhibited a cyclic hardening to saturation, while in specimens with the small particles a cyclic softening was observed after initial hardening. In the specimen with large particles, dislocations were uniformly distributed under all applied stress amplitudes, whereas the specimens bearing small particles, in which cyclic softening occurred exhibited clearly developed slip bands. The cyclic softening for the latter specimen was explained by particle shearing within the strongly strained slip bands. The width of precipitate free zones (PFZs) has been found to be one of the factors affecting the fatigue life of the specimens at 423K. The two-step aging decreases the width of PFZs, resulting in increase in the fatigue life.

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Nakane, Kazuaki, Koshiro Mizobe, Edson Costa Santos, and Kida Katsuyuki. "The Quantization of the Structure of Fisheyes via Homology Method." Applied Mechanics and Materials 307 (February 2013): 409–14. http://dx.doi.org/10.4028/www.scientific.net/amm.307.409.

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Martensitic high carbon high strength SAE 52100 bearing steel is one of the main alloys used for rolling contact applications where high wear resistance are required. Due to its high fatigue strength, SAE 52100 is recently being used not only for the production of bearings but also shafts. In this work, quenched SAE 52100 steel fatigue strength under rotating bending was investigated. Especially, we focus on “fisheye around inclusion” where the fatigue crack starts. Quantitative evaluation of its optical micrograph has not been enough carried out. In order to develop easy evaluation method for the fisheye area, we apply homology technique to the optical observation.

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Averbach, B. L., Bingzhe Lou, P. K. Pearson, R. E. Fairchild, and E. N. Bamberger. "Fatigue crack propagation in carburized high alloy bearing steels." Metallurgical Transactions A 16, no. 7 (July 1985): 1253–65. http://dx.doi.org/10.1007/bf02670330.

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Wan, Biao, Jianguo Yang, and Qinghe Wang. "Evaluation of Tribological Properties of Bearing Materials for Marine Diesel Engines Utilising the Contact Voltage Method." Applied Sciences 11, no. 17 (August 25, 2021): 7811. http://dx.doi.org/10.3390/app11177811.

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The contact voltage (CV) method, which can detect miniature failures, has been tested under laboratory conditions to monitor the condition of bearings. In this study, the bearing materials for marine diesel engines, aluminium and copper alloy, were tested on a bearing fatigue wear test bench in the boundary lubrication state, which was found through tests of the different parameters. The frictional torque, the oil film thickness and the bearing temperature were measured, as well as the CV signals. The possibility of using the CV technique to monitor the condition of the bearings was also assessed by evaluating the tribological properties. After 10 h of the test, the aluminium alloy bearing was worn to the alloy layer. Then, the wear-reducing layer on the surface of the bearing slowly peeled off, and the wear was intensified. Due to its higher wear-resisting property, the amount of wear on the copper alloy bearing increased slowly. After 20 h of the fatigue wear test, the aluminium alloy bearing became severely worn, the CV characteristic was up to 81% of the initial value, the bearing temperature increased by 6.3%, and the torque value increased by 32%. This indicates that the CV method is more sensitive to wear failure. Due to better wear resistance, the copper alloy bearing showed only slightly wear and a small increase in its CV value. The main contribution is that the CV method is useful for monitoring the lubricated condition and for evaluating the tribological properties of bearings. This research has laid technical foundations for the engineering of the sliding bearing wear monitoring system based on the CV method.

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MWANZA, M. "Microstructural characterisation of fatigue crack initiation in Al-based plain bearing alloys." International Journal of Fatigue 25, no. 9-11 (September 2003): 1135–45. http://dx.doi.org/10.1016/s0142-1123(03)00148-8.

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Huang, Qing-xue, Jian-mei Wang, Li-feng Ma, and Chun-jiang Zhao. "Fatigue Damage Mechanism of Oil Film Bearing Sleeve." Journal of Iron and Steel Research International 14, no. 1 (January 2007): 60–63. http://dx.doi.org/10.1016/s1006-706x(07)60013-2.

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Amherd Hidalgo, Alexandra, Thomas Ebel, Wolfgang Limberg, and Florian Pyczak. "Influence of Oxygen on the Fatigue Behaviour of Ti-6Al-7Nb Alloy." Key Engineering Materials 704 (August 2016): 44–52. http://dx.doi.org/10.4028/www.scientific.net/kem.704.44.

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One of the challenges in PM Ti alloys is to control the impurities level. Oxygen affects the microstructure and the mechanical properties of titanium alloys. Ti-6Al-7Nb is a promising alloy to use in PM due to its outstanding biocompatibility and mechanical properties required for load bearing medical implants. In this work, the influence of the impurities content on the ductility, fatigue resistance and microstructure of Ti-6Al-7Nb alloy processed by metal injection moulding was examined. Tensile and fatigue specimens were manufactured using Ti-6Al-7Nb gas atomized powder. Depending on the thermal treatment time, various oxygen contents were introduced into the specimens. The resulting oxygen content was determined by melt extraction technique. Tensile tests and high cycle four-point bending fatigue tests at room temperature were performed. First studies about the effect of oxygen content on crack initiation and propagation were done by the observation of microstructures and fractured surfaces using light and electron microscopy (SEM).

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Xue, Wen, Ping Wang, Zhibo Dong, and Hongyuan Fang. "Nominal stress based equal fatigue bearing capacity design of HSLA steel V-shaped butt-welded joints." MATEC Web of Conferences 221 (2018): 01009. http://dx.doi.org/10.1051/matecconf/201822101009.

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Based on nominal stress, this paper proposed a fatigue life estimation method of V-shaped butt welded joints. Then, the fatigue bearing capacity of the base metal under the same fatigue load was used as design goal of the V-shaped butt welded joints and an equal fatigue bearing capacity (EFBC) design method for V-shaped butt welds was thus formed. High strength low alloy steel Q690 was chosen as the experimental material to carry out the equal fatigue bearing capacity design.

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Medved, Ivan, Oleksandr Pirogov, Andrey Romin, Vitalii Slovinskyi, and Galyna Venzhego. "Low Cycle Fatigue of Structural Alloys." Materials Science Forum 1038 (July 13, 2021): 3–8. http://dx.doi.org/10.4028/www.scientific.net/msf.1038.3.

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Metallurgy, mechanical engineering, energy, agriculture, food industry, energy, electronics, rocket and space technology – this is a far from complete list of areas of the national economy in which liquid cryogenic products (cryoproducts). The production volumes of such products and the scale of their use are constantly increasing. This is due to the fact that cryogenic temperatures (below 120 K) provide unique opportunities for the implementation of such physical phenomena and processes that do not manifest themselves under normal conditions, but are used very effectively in science and technology. The solution of fundamental scientific problems and applied problems of both promising and current importance is determined by the level of development of cryogenic technology and the degree of its practical application. The continuous expansion of the scale of production of liquid cryogenic products has led in recent years to a significant increase in the volume of production of systems for their storage and transportation. These systems, as a rule, are welded shell structures in execution, they are operated in difficult conditions of temperature and force effects. The share of their production in the total output of cryogenic engineering products is very significant, and the operating conditions are the most stressful in comparison with other types of cryogenic structures. For the manufacture of cryogenic shell structures, expensive non-ferrous alloys and special steels are used, the degree of consumption of which, taking into account the sufficient material consumption of such structures and the expanding scale of their production, is constantly increasing. Therefore, one of the most urgent for cryogenic mechanical engineering at present is the problem of reducing the material consumption of shell structures and increasing their reliability and durability. It is obvious that a solution to this problem for cryogenic engineering products can be achieved by improving the methods of their strength calculations based on taking into account the specific hardening effect of low temperature on structural alloys. The phenomenon of low-cycle fatigue of metals is associated with elastoplastic deformation of their macrovolumes. The kinetics of elastoplastic deformation processes under cyclic loading depends on the loading conditions and material properties, and the nature of these processes and their intensity have a decisive influence on the features of material destruction. If the accumulation of deformation is small, then the destruction, as a rule, is of a fatigue nature; quasi-static fracture (similar in appearance to fracture during static tests for short-term strength) occurs after the realization of the ultimate plasticity of the material. The task of assessing the bearing capacity and durability under cyclic loading conditions is extremely important. Under cyclic loading, a number of specific phenomena and factors that are difficult to take into account analytically arise, which are primarily associated with the development of fatigue damage, with the need to assess the cyclic and structural instability of materials [1]. Since such studies are very laborious and expensive, the problem of minimizing such experiments is currently urgent. In this paper, we investigate the possibility of using mathematical planning methods for experimental studies at cryogenic temperatures. Experiment planning is usually understood as the procedure for choosing the volume and conditions of testing necessary and sufficient to solve the problem with the required accuracy.

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Eastham, D. R. "Electroplated Overlays for Crankshaft Bearings." Journal of Engineering for Gas Turbines and Power 115, no. 4 (October 1, 1993): 706–10. http://dx.doi.org/10.1115/1.2906763.

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Overlays of either lead-indium or lead-tin-copper are electroplated onto both lead-bronze and aluminum alloy crankshaft bearings to improve seizure resistance and conformability during the initial running-in period. In addition, both the corrosion resistance, particularly of lead-bronze, and the effective fatigue strength of the composite bearing are improved by this layer. The life of the overlay is largely dependent upon the diffusion rate of the low melting point species to the substrate. Thus, migration of either the indium or the tin will determine both the corrosion and wear rates of the overlay. Owing to the processing requirements, aluminum bearings require a nickel or copper interlayer prior to final overlaying with either of the lead alloys. For diffusion control reasons, when depositing lead-tin-copper onto lead-bronze it is usual to have a thin nickel dam to retard the formation of copper-tin intermetallics, which under given conditions may reduce the overall strength and adhesion; lead-indium does not require such a dam on lead-bronze. The principal differences between the two overlays lie in their respective fatigue and wear properties. Thus, lead-indium has a higher fatigue strength but lower wear resistance than lead-tin-copper. This paper compares these two major overlays and considers the selection criteria for the overlay employed.

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Leupold, S., R. Schelenz, and G. Jacobs. "Method to determine the local load cycles of a blade bearing using flexible multi-body simulation." Forschung im Ingenieurwesen 85, no. 2 (March 31, 2021): 211–18. http://dx.doi.org/10.1007/s10010-021-00457-y.

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AbstractConventional methods for designing rolling bearings against fatigue assume that a bearing ring is fully rotating and that the load is ideally distributed over the rolling elements. Blade bearings in wind turbines, are operated under oscillating motions and dynamic loads. The load distribution is strongly dependent on the stiffness of the bearing rings and the surrounding structural components. This has been shown in numerous studies using FEM simulations for static load cases. In this paper a method is presented that reduces the calculation effort of the deformation of the bearing rings, so that a flexible integration into an aeroelastic mbs model of a wind turbine is possible. Thereby an average accuracy of 6.5% between FEM and mbs could be achieved. The model allows the determination of time series of the global load distribution of each raceway. By data processing of the simulation results, the number of load cycles and the maximum contact pressure for individual segments of the raceways could be determined and their fatigue probability could be estimated using the linear damage hypothesis according to Palmgren-Miner.

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Mizobe, Koshiro, Hitonobu Koike, and Katsuyuki Kida. "Influence of Thrice-Induction-Heating and Once-Quenching on Fatigue Strength of SAE52100 Steel." Advanced Materials Research 893 (February 2014): 415–18. http://dx.doi.org/10.4028/www.scientific.net/amr.893.415.

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Martensitic high-carbon high-strength SAE 52100 bearing steel is one of the main alloys used as the principal alloys for rolling contact applications. We developed a novel repeated quenching method by induction heating in order to enhance the materials strength. The steel bar passed through the heated coil several times and finally quenched by cooling water. The rotating bending fatigue tests was done in order to investigate the fatigue strength of the steel bars. The heat affected zone (HAZ) was not expanded by the heat treatment however it was found that the thrice-induction-heating and once-quenching improved the fatigue strength. These two features indicated that the size of heat affected zone does not dominate the strength of heated-samples.

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Wang, Yuan Qing, Huan Xin Yuan, and Yong Jiu Shi. "Mechanical and Fatigue Performance Tests of Cast Aluminum Alloy ZL111 Adopted in Structure." Advanced Materials Research 168-170 (December 2010): 1961–69. http://dx.doi.org/10.4028/www.scientific.net/amr.168-170.1961.

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Characteristics of aluminum alloys such as light weight, high strength-to-weight ratio and favorable corrosion resistance have brought about a bright application prospect in building structures. Wrought alloys are applicable to common beams and columns, while casting alloys can be fabricated as connectors in point-supported glass curtain wall and joints in spatial latticed structures on account of easy implement of moulding. Because of high strength, outstanding castability and remarkable mechanical properties after heat treatment, ZL111 in aluminum-silicon alloys is regarded as a desirable option. However, aluminum alloys are non-linear materials and their properties vary with casting and heat treatment modes. It is the well-marked distinction between aluminum alloy and ordinary carbon steel that special study on mechanical and fatigue performance is required. ZL111 raw materials were selected, with alloying agent and fabrication processes meeting the requirement of GB/T 1173-1995 standard. After T6 heat treatment process, test coupons were obtained by machining from raw materials. By utilization of electronic universal testing machine and cryogenic box, tensile tests at room temperature and low temperatures were performed. High-circle fatigue tests were carried out to obtain the fatigue performance of the material. Scanning electron microscope (SEM) was introduced to observe morphology of tensile and fatigue fractures. The tests revealed the relationship between mechanical property index and temperature, which indicated that the ZL111-T6 would increase in strength and plasticity. The microstructure of fractures validated and explained the macroscopic results. Furthermore, material strength at room temperature or low temperatures, stiffness and fatigue performance could satisfy bearing and normal serviceability requirement. Because of non existence of ductile-brittle transition temperature, superior corrosion resistance and outstanding castability, ZL111-T6 material is prone to fabricate complicated elements and joints withstanding cryogenic environment instead of carbon steel.

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Ali, M. S., P. A. S. Reed, and S. Syngellakis. "Comparison of fatigue performance of HVOF spray coated and conventional roll bonded aluminium bearing alloys." Materials Science and Technology 25, no. 5 (May 2009): 575–81. http://dx.doi.org/10.1179/174328408x322213.

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Xu, Xiao Jing, Seock Sam Kim, Kang Min Chen, and Q. F. Luo. "Analysis of the Failure of Turbocharger Shaft Bearing in Diesel Engines." Key Engineering Materials 297-300 (November 2005): 1376–81. http://dx.doi.org/10.4028/www.scientific.net/kem.297-300.1376.

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A sudden failure of the bearing of the turbocharger shaft in a diesel engine, with the power of 11520KW and the total running time of 2,417h, is investigated in this paper. Based on an examination of the disassembled turbocharger and a residue analysis, it was found that the failure of the turbocharger originated from a fatigue fracture of an aluminum-alloy bearing retainer (cage) on its compressor side. The axial load was a chief cause of the fatigue fracture and the looseness defects in the aluminum alloy retainer deteriorated its fatigue strength which in turn accelerated the development of fatigue cracks. After the retainer broke, the off-centered rotation of the turbocharger shaft triggered a severe impact and led to deformation, wear and a fracture of the bearing parts, ultimately resulting in the failure of the turbocharger.

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Bhaumik, Shubrajit, and Viorel Paleu. "Wear and Rolling Contact Fatigue Analysis of AISI 52100 Bearing Steel in Presence of Additivated Lubricants." Metals 11, no. 6 (June 2, 2021): 907. http://dx.doi.org/10.3390/met11060907.

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Tribological properties of lithium potassium titanate (PT), molybdenum disulphide, and tungsten disulphide-dispersed mineral oil (MO) were investigated. The sample containing 2 wt.% WS2 exhibited the lowest coefficient of friction. However, the wear scar diameters of the additivated samples were very narrow. Extreme pressure properties of mineral oil were enhanced with the addition of additives. The rolling contact fatigue results exhibited better fatigue life of the balls in MoS2 and PT-dispersed MO. Surface characterization of the balls indicated more pitting on the balls of the MO and WS2-dispersed MO as compared to MoS2 and PT, indicating a stable film in the case of MoS2 and PT, which was confirmed by the presence of additives on ball surfaces by Raman spectrograph. The results of extended rolling contact fatigue tests proved that PT-added mineral oil provided the highest life cycles of the tested balls, followed by MoS2 and WS2-added mineral oil; thus, indicating PT as a plausible alternative to MoS2 and WS2.

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Gu, Chao, Min Wang, Yanping Bao, Fuming Wang, and Junhe Lian. "Quantitative Analysis of Inclusion Engineering on the Fatigue Property Improvement of Bearing Steel." Metals 9, no. 4 (April 24, 2019): 476. http://dx.doi.org/10.3390/met9040476.

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The fatigue property is significantly affected by the inner inclusions in steel. Due to the inhomogeneity of inclusion distribution in the micro-scale, it is not straightforward to quantify the effect of inclusions on fatigue behavior. Various investigations have been performed to correlate the inclusion characteristics, such as inclusion fraction, size, and composition, with fatigue life. However, these studies are generally based on vast types of steels and even for a similar steel grade, the alloy concept and microstructure information can still be of non-negligible difference. For a quantitative analysis of the fatigue life improvement with respect to the inclusion engineering, a systematic and carefully designed study is still needed to explore the engineering dimensions of inclusions. Therefore, in this study, three types of bearing steels with inclusions of the same types, but different sizes and amounts, were produced with 50 kg hot state experiments. The following forging and heat treatment procedures were kept consistent to ensure that the only controlled variable is inclusion. The fatigue properties were compared and the inclusions that triggered the fatigue cracks were analyzed to deduce the critical sizes of inclusions in terms of fatigue failure. The results show that the critical sizes of different inclusion types vary in bearing steels. The critical size of the spinel is 8.5 μm and the critical size of the calcium aluminate is 13.5 μm under the fatigue stress of 1200 MPa. In addition, with the increase of the cleanliness of bearing steels, the improvement of fatigue properties will reach saturation. Under this condition, further increasing of the cleanliness of the bearing steel will not contribute to the improvement of fatigue property for the investigated alloy and process design.

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Baudry, G., J. Saleil, G. Giroud, G. Duplomb, J. H. Bulit, D. Girodin, G. Dudragne, and G. Jacob. "Fatigue property evaluation of bearing steels issued from rotary continuous casting." Revue de Métallurgie 89, no. 10 (October 1992): 877–86. http://dx.doi.org/10.1051/metal/199289100877.

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Grądzka-Dahlke, Małgorzata. "Comparison of Functional Properties of Thin Layers on Titanium and Cobalt Implant Alloys." Defect and Diffusion Forum 297-301 (April 2010): 1053–58. http://dx.doi.org/10.4028/www.scientific.net/ddf.297-301.1053.

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The development of arthroplastics places high demands on the materials used for load-bearing elements of orthopedic implants. The most common of implant materials are titanium and cobalt alloys due to their excellent mechanical properties and biocompatibility. Titanium alloys have desirable properties, such as relatively low modulus, good fatigue strength, formability, machinability, superior corrosion resistance and so are frequently used for long-term implants. However, poor wear resistance limits their application for tribological systems of artificial joints. Research on improvement of titanium alloys tribological properties have been undertaken, mainly by using thin coatings. The TiN-layers are reported to be most promising in biomedical applications such. Many authors stress that application of TiN layer improve wear resistance of titanium implant alloys. Presented work is focused on comparison of effect of TiN coating on properties of TiAlV and CoCrMo implant alloys. The structure, microhardness, corrosion resistance as well as tribological properties were analysed. The research did not confirmed the good properties of titanium alloy with TiN coating. The results show that matrix metal hardness definitely affects the efficiency of TiN layers.

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Watanabe, Chihiro, and Ryoichi Monzen. "Low-Cycle Fatigue Behavior of an Al-Mg-Si Alloy with and without a Small Addition of Sc." Materials Science Forum 654-656 (June 2010): 938–41. http://dx.doi.org/10.4028/www.scientific.net/msf.654-656.938.

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Low-cycle fatigue behavior of a wrought Al-0.8wt%Mg-0.7wt%Si alloy with and without 0.27wt%Sc has been investigated at room temperature under constant plastic-strain amplitudes. After peak-aging treatments, both the alloys had fine lath-shaped β' precipitates. In the Sc-containing alloy, spherical Al3Sc precipitates of about 11 nm in diameter were co-existed. The alloy with Sc exhibited cyclic hardening to saturation, while the alloy without Sc showed clear cyclic softening after initial hardening. Transmission electron microscopy observation revealed that slip band structures were developed in the Sc-free alloy. Within the slip bands, shearing of the β' precipitates by moving dislocations was often observed. The cyclic softening in the alloy without Sc can then be explained by a loss of precipitation strengthening effect through the precipitation destruction within strongly-strained slip bands. In the Sc-bearing alloy, owing to the existence of non-shearable Al3Sc precipitates, dislocations were uniformly distributed, resulting in the absence of the cyclic softening.

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Koike, Hitonobu, Edson Costa Santos, Katsuyuki Kida, Takashi Honda, and Justyna Rozwadowska. "Effect of Repeated Induction Heating on Fatigue Crack Propagation in SAE 52100 Bearing Steel." Advanced Materials Research 217-218 (March 2011): 1266–71. http://dx.doi.org/10.4028/www.scientific.net/amr.217-218.1266.

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Martensitic high carbon high strength SAE 52100 bearing steel is one of the main alloys used for rolling contact applications when high wear and fatigue resistance are required. Refining the microstructure of steel improves its mechanical properties (e.g. toughness). In this work SAE 52100 specimens were exposed to repeated induction heating process and rotation bending tests were performed using single- and repeatedly heat-treated material in order to investigate the influence of this cyclic heat treatment on the mechanical properties of SAE 52100. In an attempt to determine the effect of the repeated induction heating and quenching on the material, we focused our observations on the internal fatigue “fisheye" cracks. It was noted that crack propagation was successfully halted by the refined microstructure in heat affected zone, therefore it can be concluded that repeated induction heating and quenching processes help to slow down the propagation of fisheye cracks in SAE52100 steel bars.

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Beer, O. "Heat Treatment and Properties of High-Temperature Steels for Rolling Bearings." HTM Journal of Heat Treatment and Materials 76, no. 2 (April 1, 2021): 155–71. http://dx.doi.org/10.1515/htm-2021-0001.

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Abstract It is demonstrated that high speed steels are suitable for manufacturing of heat resistant rolling element bearings especially for applications in aero engines. A detailed analysis of heat treating processes and metallurgical evaluation shows how the properties of these steels grades can be adjusted to meet the specific requirements for engine bearings. Based on results from rig testing it is shown how variations in heat treating parameters can influence the rolling contact fatigue performance. The role of carbides, a typical constituent of high speed steels, on bearing applications is discussed in detail. The high level of heat resistance of high speed steels allows a nitriding in addition to the conventional heat treatment. By nitriding an increase in hardness close to the surface can be achieved which can make bearings more robust against indentation of hard particles. ◼

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Balutch, Thomas, Bertrand Huneau, Yann Marco, Pierre Charrier, and Clément Champy. "Fatigue behaviour of an industrial synthetic rubber." MATEC Web of Conferences 165 (2018): 22004. http://dx.doi.org/10.1051/matecconf/201816522004.

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For some automotive anti-vibration applications, for instance exhaust hangers, center bearing bushes or torsional vibration dampers, temperature constraints make the use of synthetic rubbers, such as EPDM, necessary because of their better heat aging resistance compared to natural rubber. The aim of this paper is to understand the features of the fatigue behaviour of an industrial EPDM compared to the wellknown natural rubber. To do so, fatigue tests are conducted on hourglass-shaped specimens, and fracture surfaces are analysed using optical microscopy and scanning electron microscopy (SEM). It appears that every samples exhibit only one root cause of failure. Thus, two types of precursors are identified as responsible of the final fracture of samples: material’s inclusions and mold flaws. Interrupted fatigue tests are then performed and fatigued samples are observed with SEM. The built procedure allows us to follow fatigue cracks initiation and propagation along cycles, and to propose local damage mechanisms for each type of precursors. A global damage scenario is finally considered and compared to the one of natural rubber described in the literature.

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Xu, Hai-feng, Gui-lin Wu, Chang Wang, Jian Li, and Wen-quan Cao. "Microstructure, hardness and contact fatigue properties of X30N high nitrogen stainless bearing steel." Journal of Iron and Steel Research International 25, no. 9 (September 2018): 954–67. http://dx.doi.org/10.1007/s42243-018-0138-8.

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Zhu, Zhi Shou, Chun Xiao Cao, and Ming Gao Yan. "Low Cycle Fatigue Behavior of a Near-α Ti Alloy Containing Rare Earth Nd." Materials Science Forum 475-479 (January 2005): 599–602. http://dx.doi.org/10.4028/www.scientific.net/msf.475-479.599.

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Low cyclic behavior of a new type near-α titanium alloy containing rare earth Nd (Ti60) with and without dwell time introduced at maximum tensile strain has been investigated at ambient temperature and 600°C. The results show that, Ti60 alloy exhibits a cyclic softening behavior at almost all strain levels being investigated. The cyclic processes show good agreement with predictions based on the fatigue crack propagation model. At 600°C, the LCF life of Nd-bearing near-α titanium alloy is superior to that at room temperature within the investigated strain range, which indicates that Ti60 alloy is a good candidate for high temperature component under complicated load and temperature conditions. The results also show that the creep-fatigue interaction is related to the strain range applied. The creep-fatigue fracture is characterized by transgranular fracture mode due to the formation of matrix voids induced by Nd-bearing particles.

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Bolaers, F., O. Cousinard, P. Estocq, X. Chiementin, and J.-P. Dron. "Comparison of denoising methods for the early detection of fatigue bearing defects by vibratory analysis." Journal of Vibration and Control 17, no. 13 (January 17, 2011): 1983–93. http://dx.doi.org/10.1177/1077546309348853.

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The aim of this article is to show the interest of three major denoising methods for the improvement of the sensitivity of scalar indicators (crest factor, kurtosis) within the application of conditional maintenance by vibratory analysis on ball bearings. The case of a bearing in good condition of use is considered. The distribution of amplitudes in the vibratory signal is of the Gaussian kind. When the bearing is damaged, the appearance of spalling comes to disturb this signal, modifying this distribution. This modification is due to the presence of periodical impulses produced each time a rolling element meets a discontinuity on its way. Nevertheless, the presence of background noise induced by random impulse excitations can have an influence on the values of these temporal indicators. The denoising of these signals allows to improve the sensitivity of these indicators and to increase the reliability of the diagnosis.

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Zhou, Zi-long, Hai-quan Wang, Xin Cai, Hai-zhi Zang, Lu Chen, and Fu Liu. "Bearing characteristics and fatigue damage mechanism of multi-pillar system subjected to different cyclic loads." Journal of Central South University 27, no. 2 (February 2020): 542–53. http://dx.doi.org/10.1007/s11771-020-4315-0.

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35

Germain, Guenael, Franck Morel, Jean Lu Lebrun, Anne Morel, and Bertrand Huneau. "Effect of Laser Assistance Machining on Residual Stress and Fatigue Strength for a Bearing Steel (100Cr6) and a Titanium Alloy (Ti 6Al 4V)." Materials Science Forum 524-525 (September 2006): 569–74. http://dx.doi.org/10.4028/www.scientific.net/msf.524-525.569.

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The use of Laser Assisted Machining (LAM) can improve different aspects of the machinability of high strength materials. A study was undertaken to determine the optimum cutting parameters and to quantify their influence on fatigue strength according to the type of microstructure created. Two different materials were studied: a bearing steel (100Cr6 / AISI 52100) and an aeronautical titanium alloy (Ti6Al4V). In the bearing steel a significant increase of the fatigue resistance was observed due to the transformation of the surface layer into martensite. For the titanium alloy, a slight reduction in the fatigue strength was found as in this case the microstructure and residual stress state of the surface layer was less beneficial. The surface roughness has also been measured and no significant variation has been observed for different laser powers in each material.

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36

Bento, Rodrigo Teixeira, André Ferrus Filho, and Marco Antonio Fumagalli. "Structural Design and Stress Analysis of a High-Speed Turbogenerator Assembly Supported by Hydrodynamic Bearings." International Journal of Manufacturing, Materials, and Mechanical Engineering 10, no. 1 (January 2020): 54–67. http://dx.doi.org/10.4018/ijmmme.2020010104.

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Turbine and bushing bearing are the most critical components of high-speed machines. This article describes the design of a high-speed turbine supported by hydrodynamic bearings. The mathematical dimensioning and the FEM analysis are presented to validate the mechanical strength of the turbine and the bushing bearing models. Fatigue life and factor of safety were also determined. The simulations showed that the maximum Von Mises stress values obtained are associated to the centrifugal force generated by the system rotational movement. The results variation was mainly due to the properties of the materials proposed. For the turbine, 7075-T6 aluminum alloy and SAE 4340 steel obtained satisfactory behavior under a constant operating speed of 30,000 RPM. For the hydrodynamic bearing, the TM23 bronze alloy exhibited excellent results, without fracture, and low mechanical deformation. The models exhibited a great potential employment in several applications, such as biogas systems to generate electrical energy, and educational test bench for thermodynamic and tribological simulations.

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Eto, Takehiko, and Manabu Nakai. "New Process-Microstructure Method for Affordable 2024 Series Aerospace Aluminum Alloys." Materials Science Forum 539-543 (March 2007): 3643–48. http://dx.doi.org/10.4028/www.scientific.net/msf.539-543.3643.

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New affordable 2024 series aerospace aluminum alloy has been developed. Fracture toughness has been demonstrated increase in inverse proportion to the root of the distance between constituents, Cu2FeAl7, formed during ingot solidification. Higher fracture toughness material is obtained by means of combination of reduction of Fe content and wider spacing between the constituents. The fractured surface of those materials has been confirmed to show larger dimples due to the wider constituents. An outcome is the fracture toughness increases 20% through broadening the space from 75 to 140μm. Fatigue crack growth (FCG) has been governed by the morphology of dispersoids such as Cu2MnAl20, Cr2Mg3Al18 and ZrAl3, formed in homogenization process during heat treatment of ingot. In a low ΔK region, the FCG rate is slower when Cu2MnAl20 becomes larger. It is reconfirmed that the FCG rate is still faster for small dispersoids, Cr2Mg3Al18 or ZrAl3 bearing materials than Cu2MnAl20 bearing one through bridging effect of dispersoids. In a high ΔK region, on the other hands, the FCG rate becomes slower by broadening the spacing of the constituents. A new 2024 series alloy (2x24) with high fracture toughness and excellent FCG resistance has been developed on the basis of process- microstructure-structure methods.

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Rozwadowska, Justyna, Katsuyuki Kida, Edson Costa Santos, Takashi Honda, Hitonobu Koike, Yuji Kashima, K. Kanemasu, and R. Matsumoto. "Rolling Contact Fatigue of Titanium Alloys Coated by Gas Nitriding Using a Q-Sw Laser." Applied Mechanics and Materials 83 (July 2011): 191–96. http://dx.doi.org/10.4028/www.scientific.net/amm.83.191.

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The influence of gas nitriding of commercial pure titanium and Ti-6Al-4V (Ti64) alloy by using a Q-sw laser on the wear loss during rolling contact fatigue is investigated. Despite very good biocompatibility, high strength to weight ratio and corrosion resistance, the tribological properties of titanium alloys are inferior to those of other metal alloys, such as steel. Fretting and wear related aspects become important issues when titanium alloys are used in rolling contact applications. Titanium bearings are employed in applications requiring high strength, light weight, and minimum maintenance (for example, aerospace and defense industries). In this work, a Q-sw laser was used to coat pure commercial titanium and Ti-6Al-4V bearings with TiN in a closed chamber in nitrogen atmosphere. The samples were tested under water by using a thrust-type rolling contact fatigue machine. The microstructure, morphology and crystallographic texture of the layers were observed by laser confocal microscope, scanning electron microscope and electron backscatter diffraction (EBSD). By optimizing the laser processing parameters, such as laser scanning speed, power and beam diameter, thin TiN coats of 1 to 3 mm were produced. The wear loss of the coated samples was at least ten times lower than that of the uncoated bearings.

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Oh, Chung Seog, Philip Park, Yong Hak Huh, Soon Gyu Ko, Don Young Hwang, and Hyeon Mo An. "Fatigue Crack Growth Behavior of Corner Cracks under LBH Loading." Key Engineering Materials 297-300 (November 2005): 128–36. http://dx.doi.org/10.4028/www.scientific.net/kem.297-300.128.

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This investigation aims at doing some durability and damage tolerant (DaDT) tests with 2124-T851 aluminum specimens having corner cracks under a random history, correlating with the simulation results from AFGROW and then drawing some conclusions from those comparisons. Two hydraulic actuators and a homemade Wood’s alloy grip are employed to do the test. The surface crack lengths are measured by a traveling microscope and used as a reference for the later fractography. The crack penetration and the total lives are about 17 and 27 blocks, respectively. The crack length and depth are evaluated by the fractography after completing each test and used to grasp the shape change. The Forman equation is used to simulate the fatigue crack growth behavior according to a bearing stress ratio extensively. The crack penetration life is decreased as the bearing stress ratio increases. The crack aspect ratio is very dependent on the bearing stress ratio. The LBH loading accelerates the fatigue crack growth in the crack depth direction but decelerates that in the length direction until crack penetration.

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40

Shankayi, M., H. Soleimanimehr, M. R. Rahmanabadi, and A. R. Shafighi. "Bearing Design Simulation in Direct Extrusion of AA2024 Using Finite Element." Advanced Materials Research 445 (January 2012): 263–68. http://dx.doi.org/10.4028/www.scientific.net/amr.445.263.

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Extrusion is a metal forming process which involves plastic deformations. Economic significance of extrusion is due to its material efficiency, labor costs reduction, elimination of intermediate treatments, better output quality, and high production rates. Bearing length is one of the important features in extrusion dies. The aim is to make all the material points in outgoing profile have the same flow velocity, so in an effective design the flow velocity of thick features is controlled to be same as for thinner features. AA2024 alloy is widely used in military and aerospace industries. It has a high heat treatment capacity and strength to weight ratio. Other characteristics include excellent toughness, fatigue behavior, crack growth resistance, and machinability. However it is difficult to extrude. The purpose of this paper is to determine a strategy for designing bearings in direct extrusion dies which are used in production of parts from AA2024 aluminum alloy. Proper design of bearings is among factors of controlling material flow in this process and has an important role in scrap rate reduction. Using ABAQUS finite element software package, direct extrusion process is simulated. Results are explored and investigated for different conditions and finally, an efficient bearing configuration is introduced. Finally, it is shown that using uniform bearing for complicated sections is not possible. Optimum design is also presented using finite element analysis.

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41

Negrea, Alexis Daniel, Ileana Nicoleta Popescu, Mihǎiţǎ Nicolae Ardeleanu, Claudiu Nicolicescu, and Carmen Otilia Rusǎnescu. "Researches and Finite Element Simulations of Radial Loading Deformations Applied to Steel Ball Bearings." Advanced Engineering Forum 34 (October 2019): 109–14. http://dx.doi.org/10.4028/www.scientific.net/aef.34.109.

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The appearance of quick wear of rolling paths and rolling elements (balls) through contact fatigue phenomena and through surface defects lead to a decrease in the life of ball bearings in service. One of the causes is the interruption of the lubricating film between surfaces with relative motion under load conditions and high speeds, which leads to plastic micro-deformations and micro-welding between contact surfaces. Diagnosing defects by visual observation involves disassemble of the bearing and is an ineffective method of investigation in serial production. In this context, the necessity of: (i) comparative study of the stresses to which two types (100Cr6 steel and 100CrMnSi6-4 steel type) of radial ball bearings are subjected, (ii) the influence of contact between the ball and the inner ring during rotation, and (iii) the analysis with Finite Element Method (FEM) of the deformations occurring at the application of radial bearing forces. FEM is a current approach to real phenomena in mechanical assemblies, which allows a validation of study assumptions; the results of FEM can lead to the detection of tribological causes of increased bearing wear at inner ring to bearing balls contact. In this paper, FE simulation of radial loading deformations was performed in SolidWorks software using the Simulation module and the stresses and deformations in the bearing rings for the two materials were obtained. It has been found that the stresses that appear during simulations are similar for both materials and do not exceed the limits allowed for heavy duty steel bearings.

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42

Rozwadowska, Justyna, Katsuyuki Kida, Edson Costa Santos, Takashi Honda, Hitonobu Koike, Yuji Kashima, and Kenji Kanemasu. "Wear Resistance Improvement of Titanium Bearings by Laser Gas Nitriding." Advanced Materials Research 217-218 (March 2011): 988–93. http://dx.doi.org/10.4028/www.scientific.net/amr.217-218.988.

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The influence of gas nitriding of commercial pure titanium and Ti-6Al-4V (Ti64) alloy by using a Q-sw laser on the wear loss during rolling contact fatigue is investigated. Despite very good biocompatibility, high strength to weight ratio and corrosion resistance, the tribological properties of titanium alloys are inferior to those of other metal alloys, such as steel. Fretting and wear related aspects become important issues when titanium alloys are used in rolling contact applications. Titanium bearings are employed in applications requiring high strength, light weight, and minimum maintenance (for example, aerospace and defense industries). In this work, a Q-sw laser was used to coat pure commercial titanium and Ti-6Al-4V bearings with TiN in a closed chamber in nitrogen atmosphere. The samples were tested under water by using a thrust-type rolling contact fatigue machine. The microstructure, morphology and crystallographic texture of the layers were observed by laser confocal microscope, scanning electron microscope and electron backscatter diffraction (EBSD). By optimizing the laser processing parameters, such as laser scanning speed, power and beam diameter, thin TiN coats of 1 to 3 m were produced. The wear loss of the coated samples was at least ten times lower than that of the uncoated bearings.

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43

Jiang, Shu Nong, and Shi Yuan Xu. "Influence of Surface Conditions on the Fatigue Behavior of A357 Aluminum Alloy." Materials Science Forum 850 (March 2016): 113–19. http://dx.doi.org/10.4028/www.scientific.net/msf.850.113.

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The influence of surface conditions on the fatigue behavior A357 aluminum alloy was studied in this paper. Four-point bending fatigue tests method were performed to obtain the fatigue strength of A357 cast aluminum alloy specimens with different surface conditions. A joint bearing rig was designed to minimize the experimental error caused by the misalignment associated with a four-point bend test. The results showed that the fatigue strength of specimens with as-cast surfaces was higher those with machined surface roughness of Ra=1.6μm and 3.2μm, while lower than that with Ra=0.4μm. Optical microscope (OM) and scanning electron microscope (SEM) observations, indicating that the fatigue cracks initiate from machined grooves for specimens with roughness of Ra=1.6μm and 3.2μm, while subsurface crack initiates from cast defects inside the specimen with roughness of Ra=0.4. For specimens with as-cast surface, the fatigue cracks initiate from the surface irregularities or cast defects near the surface.

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44

Fu, Hanwei, and Pedro E. J. Rivera-Díaz-del-Castillo. "A unified theory for microstructural alterations in bearing steels under rolling contact fatigue." Acta Materialia 155 (August 2018): 43–55. http://dx.doi.org/10.1016/j.actamat.2018.05.056.

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45

Tsuji, Kenya, Koshiro Mizobe, and Katsuyuki Kida. "Development of Fracture Surface Etching (FSE) Method around Non-Metallic Inclusion of SUJ2 Steel." Materials Science Forum 971 (September 2019): 65–69. http://dx.doi.org/10.4028/www.scientific.net/msf.971.65.

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High-carbon high-strength JIS-SUJ2 bearing steel is one of the alloys used as rolling contact applications which need high wear resistance. This high hardness material is broken from non-metallic inclusions under fatigue stress. In this work, we developed a new observation method “fracture surface etching (FSE)” in order to observe the material microstructure on the fracture surface. We succeeded to draw clear grain boundaries on the fracture surfaces and closely observed the material microstructure around the crack origins by the FSE method. We concluded that the crack initiation area boundary is not formed by only the grain boundary, and the grain size around the Al2O3 inclusion on the fracture surface was similar to that of the flat surface which does not have inclusions before fatigue testing.

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46

Venugopal, Arvinthan, Roslina Mohammad, Md Fuad Shah Koslan, Ashaari Shafie, Alizarin bin Ali, and Owi Eugene. "Crack Growth Prediction on Critical Component for Structure Life Extension of Royal Malaysian Air Force (RMAF) Sukhoi Su-30MKM." Metals 11, no. 9 (September 14, 2021): 1453. http://dx.doi.org/10.3390/met11091453.

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The critical aircraft structure, being the load-bearing members, is a vital component for any aircraft. The effect of fatigue loading, operating conditions, and environmental degradation has caused the structural integrity of the airframe to be assessed for its airworthiness requirement. Using the fatigue design concept of Safe Life, the RMAF adopts the Aircraft Structure Integrity Program (ASIP) to monitor the structural integrity of its critical components. RMAF has produced the task card using the engineering analysis concept on the aircraft’s critical structure. Various Computer-Aided Engineering (CAE) methods were used, and for this analysis, the Crack Growth Prediction method was used to determine the crack growth behavior and its ultimate failure point in case of any crack occurrences. Although there are six critical locations, the wing root is chosen since it has the highest possibility of fatigue failure. The analytical methods which were discussed are Crack Growth Analysis and Low Cycle Fatigue. For the numerical method, NX Nastran was used for the simulation of crack growth. The result from the crack growth analysis was validated with the numerical result. The conclusion is that, based on the fatigue life cycle, the wing root structure condition is not affected by severe damage, and its failure is approximately around 30 to 100 years for both the through hole and through side crack. Thus, its structural life can be extended. The research outcome will be on the extension of the structure life of the aircraft wing.

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An, Xueliang, Zhiyue Shi, Haifeng Xu, Cunyu Wang, Yuhui Wang, Wenquan Cao, and Jinku Yu. "Quantitative Examination of the Inclusion and the Rotated Bending Fatigue Behavior of SAE52100." Metals 11, no. 10 (September 23, 2021): 1502. http://dx.doi.org/10.3390/met11101502.

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This study investigated the effect of maximum inclusion on the life of SAE52100 bearing steel processed by two different melting routes, vacuum induction melting plus electroslag remelting (VIM + ESR), and basic oxygen furnace plus ladle furnace plus vacuum degassing process (BOF + LF + RH) by the metallographic method, Aspex explorer, and rotated bending fatigue test. The rotated bending method was applied to examine the maximum inclusion size in a satisfactory manner, whereas both the metallographic method and Aspex explorer underestimated the result. Regardless of the characterization methods, the results show that the total number of inclusions in VIM + ESR melted steel is significantly higher than that in BOF + LF + RH processed steel, but the maximum inclusion size of VIM + ESR melted steel is significantly smaller than that of the BOF + LF + RH degassed steel. The distribution of the maximum inclusion size could be well fitted by the inverse Weibull distribution and could be well applied to reveal the different inclusion size distribution based on the data examined by the rotated bending fatigue method. Finally, a new equation was proposed to establish the relationship among the loading stress amplitude, rotated bending fatigue number, and the maximum inclusion size.

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48

Xiao, Wei, Yan-ping Bao, Chao Gu, Min Wang, Yu Liu, Yong-sheng Huang, and Guang-tao Sun. "Ultrahigh cycle fatigue fracture mechanism of high-quality bearing steel obtained through different deoxidation methods." International Journal of Minerals, Metallurgy and Materials 28, no. 5 (May 2021): 804–15. http://dx.doi.org/10.1007/s12613-021-2253-y.

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Gu, Chao, Wen-qi Liu, Jun-he Lian, and Yan-ping Bao. "In-depth analysis of the fatigue mechanism induced by inclusions for high-strength bearing steels." International Journal of Minerals, Metallurgy and Materials 28, no. 5 (February 10, 2021): 826–34. http://dx.doi.org/10.1007/s12613-020-2223-9.

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Zhang, Jiao, Xi Li, and Hao Xie. "Fatigue Finite Element Analysis of Certain Type of EMU Gearbox Box." Applied Mechanics and Materials 789-790 (September 2015): 236–40. http://dx.doi.org/10.4028/www.scientific.net/amm.789-790.236.

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EMU gearbox is a key component of high-speed train, the reliability of the gearbox will directly affect the operational safety of EMU. The box of EMU gearbox is with light alloy materials, bearing structure, so the box is subjected to greater loads and shock and vibration. Designers most take into account the static strength and stiffness of the box, ignore the fatigue failure. Fatigue failure is the leading cause of mechanical structural failure, while the peak load cycle fatigue failure is often far less than estimated in accordance with the static fracture analysis "safe" load, so the EMU gearbox box’s fatigue analysis is needed. Combining high-speed EMU gearbox actual operating conditions, using finite element method to do fatigue analysis of the gearbox box while the analysis result is evaluated and amended by the Smith schematic analysis method.

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Journal articles on the topic 'Fatigue of bearing alloys'

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