Journal articles: 'Aluminium Beads'

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Bansal, Abanesh kumar, and Vishal Pande. "Development and Evaluation of Dual Cross-Linked Pulsatile Beads for Chronotherapy of Rheumatoid Arthritis." Journal of Pharmaceutics 2013 (December 18, 2013): 1–8. http://dx.doi.org/10.1155/2013/906178.

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In the present investigation, pulsatile release beads were prepared by ionic gelation technique. Lornoxicam dual cross-linked beads were prepared by dropping dispersed phase of lornoxicam, pectin, and sodium alginate into the dispersion phase of different concentrations of calcium chloride solution followed by aluminium chloride solution. The formulated beads were further coated by Eudragit L & S 100 in the ratio 1 : 2 w/w in order to achieve desired lag time. In vitro release study showed lag time of 5–8 h before release of lornoxicam from the formulated beads. Thus, formulated dual cross-linked beads when administered at bed time may release lornoxicam when needed most for chronotherapeutics of early morning rheumatoid arthritis attacks in chronic patients.

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Salahuddin, Bidita, Shazed Aziz, Shuai Gao, Md Shahriar A. Hossain, Motasim Billah, Zhonghua Zhu, and Nasim Amiralian. "Magnetic Hydrogel Composite for Wastewater Treatment." Polymers 14, no. 23 (November 22, 2022): 5074. http://dx.doi.org/10.3390/polym14235074.

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Nanocomposite hydrogels are highly porous colloidal structures with a high adsorption capacity, making them promising materials for wastewater treatment. In particular, magnetic nanoparticle (MNP) incorporated hydrogels are an excellent adsorbent for aquatic pollutants. An added advantage is that, with the application of an external magnetic field, magnetic hydrogels can be collected back from the wastewater system. However, magnetic hydrogels are quite brittle and structurally unstable under compact conditions such as in fixed-bed adsorption columns. To address this issue, this study demonstrates a unique hydrogel composite bead structure, providing a good adsorption capacity and superior compressive stress tolerance due to the presence of hollow cores within the beads. The gel beads contain alginate polymer as the matrix and MNP-decorated cellulose nanofibres (CNF) as the reinforcing agent. The MNPs within the gel provide active adsorption functionality, while CNF provide a good stress transfer phenomenon when the beads are under compressive stress. Their adsorption performance is evaluated in a red mud solution for pollutant adsorption. Composite gel beads have shown high performance in adsorbing metal (aluminium, potassium, selenium, sodium, and vanadium) and non-metal (sulphur) contaminations. This novel hybrid hydrogel could be a promising alternative to the conventionally used toxic adsorbent, providing environmentally friendly operational benefits.

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B, Naga Roopini, and Pradeep Kumar M. "Formulation and Evaluation of Mucoadhesive Beads of Dexamethasone." International Journal of Clinical Pharmacokinetics and Medical Sciences 3, no. 2 (August 21, 2023): 63–71. http://dx.doi.org/10.26452/ijcpms.v3i2.504.

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The goal of the current study was to formulate and evaluate mucoadhesive Dexamethasone beads to significantly lengthen the duration of the drug's stay in the GI system to treat Crohn’s disease. Dexamethasone is a corticosteroid that acts as an anti-rheumatic and anti-inflammatory. To decrease the dosage frequency Dexamethasone adhesive beads were formulated for Intimate contact with the underlying absorption surface is made possible by a prolonged stay at the location, which enhances the drug's therapeutic effectiveness. In the current study, calcium chloride and aluminium chloride were utilised as cross-linking agents to create Dexamethasone mucoadhesive beads employing adhesive polymers like sodium alginate, HPMC, and Eudragit L-100. The prepared beads' entrapment efficiencies ranged from 57.15 to 99.16%. Regarding entrapment effectiveness, particle size, surface properties, and in-vitro drug release experiments, the impact of bioadhesive polymers and cross-linking ions was assessed. The MPS-7 delayed the drug's release for 12 hours, which may be related to the cross-linking agent aluminium chloride. According to drug release kinetics, all of the formulations were more linear concerning zero order (r2=0.99) than concerning first order (r2=0.751 to 0.828). Super Case 2 Transport was discovered to be the precise release mechanism.

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Egwuonwu, Njoku, Romanus. "Evaluation of the Heat Transfer Performance of Stearic Acid PCM/ Porous Aluminium Thermal Composite Structures for Heat Storage Applications." Mediterranean Journal of Basic and Applied Sciences 06, no. 02 (2022): 74–84. http://dx.doi.org/10.46382/mjbas.2022.6209.

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Phase change material (PCM) thermal composites consisting of porous aluminium/stearic acid phase change material have been produced for heat storage applications. Porous aluminium/stearic acid composite structures were produced by infiltrating stearic acid PCM into open- cell porous aluminium materials prepared by using dissolvable spherical salt beads in combination with vacuum casting process. Scanning electron microscopic analysis has been used to characterize the empty porous aluminium materials and the results reveal a cellular structure consisting of spherical pores which are interconnected with smaller windows. The thermal response of empty porous aluminium structures and those infiltrated with stearic acid was measured using an infrared camera. The result showed that the heat transfer performance of the PCM thermal composites was significantly improved and largely dependent on the relative density of the porous structures.

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Giri, Tapan Kumar, Tania Adhikary, and Subhasis Maity. "Development of Capsaicin Loaded Hydrogel Beads for In vivo Lipid Lowering Activities of Hyperlipidemic Rats." Drug Delivery Letters 9, no. 2 (May 15, 2019): 108–15. http://dx.doi.org/10.2174/2210303109666190128151605.

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Objective: The presence of capsaicin in the diet has been revealed to enhance energy expenditure and it has been used in anti-obesity therapy. The present work investigated the potential antihyperlipidemic effect of capsaicin loaded hydrogel beads on hyperlipidemic rats. Hydrogels are three dimensional, hydrophilic, polymeric networks capable of imbibing large amounts of water or biological fluids. Methods: Capsaicin loaded hydrogel beads were prepared by the ionotropic gelation method using Aluminium Chloride (AlCl₃) as a cross-linking agent. The characterization of hydrogel beads was carried out by X-ray Diffraction (XRD), Differential Scanning Calorimetry (DSC), and Scanning Electron Microscopic (SEM) analysis. Results: The surface morphology revealed that the prepared beads were spherical in shape. XRD and DSC study of the hydrogel beads revealed that the drug was homogeneously dispersed in the hydrogel matrix. The beads showed pH sensitive behavior and when the medium pH was changed from 1.2 to 7.4, the capsaicin release was considerably increased. 100mg/kg body weight of Triton was injected intraperitoneally in rats to induce hyperlipidemia and it showed elevated levels of serum cholesterol and triglyceride. Capsaicin loaded hydrogel beads were administered to normal and hyperlipidemic rats for 7 days and the prepared hydrogel beads were significantly reduced high lipid profile in comparison to free capsaicin. Conclusion: The results clearly demonstrated that hydrogel beads can be used as a potential carrier for delivery of capsaicin to reduce lipid profile.

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Grum, Janez, and Uros Zupanc. "Surface Analysis after Shot Peening Processing of ENAW 7075 Aluminium." Materials Science Forum 589 (June 2008): 385–90. http://dx.doi.org/10.4028/www.scientific.net/msf.589.385.

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Shot peening has been a very important and well-known surface cold-hardening process applicable to various machine parts and tool surfaces for quite a long time since it improves fatigue strength and corrosion resistance of stressed surfaces. Hardening by shot peening provides, because of plastic deformation, an increase in hardness and induces compressive residual stresses in the thin surface layer, which reduces material fatigue and prevents the generation and propagation of cracks. The present paper reports of results of shot peening hardening of specimens made of 7075-T651 aluminium. They were surface-hardened by steel shots M170 with Almen hardening intensity of 8A and 12A respectively and by glass beads GP165 with Almen hardening intensity of 12A. The steel shots and glass beads had the same diameter but differed considerably in hardness and density. The surface condition after shot peening processing was assessed in terms of surface integrity, which establishes a relation between processing conditions and roughness state and hardened-layer depth supported by an analysis of residual-stress variations.

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Merklein, Marion, and Martin Grüner. "Mechanical Behaviour of Ceramic Beads Used as Medium for Hydroforming at Elevated Temperatures." Key Engineering Materials 410-411 (March 2009): 61–68. http://dx.doi.org/10.4028/www.scientific.net/kem.410-411.61.

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The need of light weight construction for high efficient vehicles leads to the use of new materials like aluminium and magnesium alloys or high strength and ultra high strength steels. At elevated temperatures the formability of steel increases as the flow stresses decrease. Forming high complex geometries like chassis components or components of the exhaust system of vehicles can be done by hydroforming. The hydroforming process by oils is limited to temperatures of approximately 300 °C and brings disadvantages of possible leakage and fouling. Using granular material like small ceramic beads as medium could be an approach for hydroforming of ultra high strength steels like MS W1200 and CP W800 at temperatures up to 600 °C. The material properties of granular material are in some points similar to solid bodies, in other points similar to liquids. For understanding and simulation of the behaviour of the medium a basic characterisation of ceramic beads with different ball diameters is necessary. Powder mechanics and soil engineering give ideas for experimental setups. For the conversion of these approaches on the one hand the behaviour of the ceramic beads itself has to be characterized, on the other hand the contact between a blank and the beads have to be investigated. For the tests three different kinds of spheres with a diameter between 63 microns and 850 microns are used. In unidirectional compression test compressibility, pressure distribution in compression direction and transversal compression direction and the effect of bead fracture are investigated. The tests are carried out at different compression velocities and for multiple compressions. For determination of friction coefficients between blank and beads and determination of shear stress in bulk under compression a modified Jenike-Shear-Cell for use in universal testing machines with the possibility of hydraulic compression of the beads is built up. The gained data can be used for material modelling in ABAQUS using Mohr-Coulomb or Drucker-Prager model.

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Cheng, Zhenmin, Gang Luo, Yanling Tang, Dan Ling, Zhaoxuan Chen, Peng Liu, and Bo Zhang. "External Wetting Efficiency in a Three-Phase Fixed Bed Loaded with Porous and Non-Porous Packings." Processes 10, no. 1 (January 10, 2022): 135. http://dx.doi.org/10.3390/pr10010135.

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Films and rivulets are the two basic forms of dynamic liquid in a three-phase fixed bed (trickle bed), which determines the wetting efficiency of the catalyst. This paper is devoted to the conflicting wetting performance observed between non-porous glass beads and less wettable porous alumina, and a parallel zone model is applied to resolve the complex liquid flow texture. It shows in both cases of glass beads and aluminium pellets, the pressure drop, film flow and rivulet flow fractions all display pronounced multiplicities along with the liquid flow rates in increasing and decreasing branches, although the rivulet flow fraction is reduced to 0 in the liquid decreasing branch started from pulsing flow in both cases. Different from the glass beads, there is almost no wetting efficiency difference for the alumina pellets with respect to liquid flow rate increasing or decreasing, which is in agreement with the dynamic liquid holdup measurements. The liquid is significantly more uniformly distributed over the crosssection in the Al2O3 bed since rivulet flow is much reduced than in the case of glass beads.

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9

Olczak, Jerzy. "W sprawie wytwórczości szklarskiej w celtyckim oppidum w Starym Hradisku na Morawach." Folia Praehistorica Posnaniensia 13 (November 1, 2018): 215–29. http://dx.doi.org/10.14746/fpp.2005.13.15.

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Discussion presented in the article is based upon analysis of glass fragments from the late La Tene oppidum. Existence of the jewellery manufacture workshop in Stare Hradisko, producing bracelets and possibly also beads of dark-blue, dark-yellow and green glass of external origin, is speculated based upon chemical composition of 5 fragments as well as morphological analysis. Further complex studies are postulated, which will facilitate unequivocal testing of the speculation about existence of glass works in StareHradisko. Analysed samples revealed presence of the soda-calcium-aluminium-silicon as well as the soda-calcium-lead-aluminium-silicon glass.

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Göttmann, Alexander, Chris Mertin, Linda Mosecker, Andreas Naumov, and Markus Bambach. "Properties of Friction Stir Welded Blanks Made from DC04 Mild Steel and Aluminum AA6016." Advanced Materials Research 769 (September 2013): 237–44. http://dx.doi.org/10.4028/www.scientific.net/amr.769.237.

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Due to increasing demands for lightweight structures in automotive applications the use of sheet metal components made from aluminium alloys is a promising approach for weight reduction. The combination of steel and aluminium in car bodies may be an interesting alternative compared to a monolithic material design. The weight of structural parts of a car body shell can be reduced if dedicated parts consist of aluminium instead of steel. This approach allows for an optimal exploitation of the material properties of both materials, bringing high strength into highly loaded areas while areas subject to lower loads are equipped with lower strength and weight. However, a multi-material design combining steel and aluminium demands for suitable joining methods, especially if a forming operation is applied to the welded sheets. In conventional fusion welding processes the formation of intermetallic phases due to the metallurgical affinity of aluminium and iron is a serious problem. Recent developments in regulated cold metal transfer (CMT) welding technologies at the Institute of Welding Technology and Joining Technology (ISF) at the RWTH Aachen promise an appropriate solution to this problem. Due to a digitally regulated arc technology, the heat input in CMT is reduced to a minimum. However, the inevitable formation of a welding bead in arc processes with filler material is a criterion of exclusion in the case of production of welds for car body shells. To achieve an optimal appearance of the body shell, the welding beads need to be removed from both sides of the sheet in a second manufacturing step. Hence, to avoid further costs, it seems expedient to search for alternative welding technologies. Friction stir welded (FSW) joints show relatively even welding beads. Furthermore, this joining method is characterised by a low process temperature, which is considerably below the melting temperature of the base materials. Hence, FSW is a promising joining technique to produce tailored blanks out of aluminium and steel. The main objective of the present paper is the evaluation of suitable process parameters for the production of FSW butt joints with a thickness of 1 mm made from the aluminium alloy AA6016-T4 and the mild steel DC04. Welding experiments using a varying rotational speed, tool offset, tool velocity, tool plunge depth and tool tilt angle were carried out. To identify the best parameters in terms of the strength of the joint, tensile tests were performed. It is shown, that an amount of approximately 85% of the tensile strength of the base material AA6016 can be achieved. Using SEM the formation of the fracture surfaces was analysed. Different fracture types were identified and the possible reasons for their occurrence are discussed. It is shown that in the case of optimal joining procedure the failure occurs in the thermomechanically affected zone in the aluminium sheet, were the plastic deformation is low. Additionally, thermography has been employed to evaluate the temperature distribution during the process. In metallographic investigations it was found that during welding the microstructure of the aluminium base material changes due to plastic deformation and temperature increase in the area of the weld seam. Using hardness measurements the change of the mechanical properties in the contact zone of both base materials and in the heat affected zone was examined. Finally, an outlook is given with respect to the possibilities of producing FSW welded sheets that can be formed using conventional deep-drawing.

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Akbari, Masoumeh, Shanmuganathan Gunalan, Benoit P. Gilbert, Hong Guan, and Balachandren Baleshan. "Bearing behaviour of aluminium sub-heads with removable beads in façade systems." Structures 32 (August 2021): 1934–54. http://dx.doi.org/10.1016/j.istruc.2021.03.055.

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Reddy, K. V. Ramana, and M. V. Nagabhushanam. "PROCESS AND PARAMETERS AFFECTING DRUG RELEASE PERFORMANCE OF PREPARED CROSS-LINKED ALGINATE HYDROGEL BEADS FOR EZETIMIBE." International Journal of Pharmacy and Pharmaceutical Sciences 9, no. 2 (February 1, 2017): 254. http://dx.doi.org/10.22159/ijpps.2017v9i2.16235.

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Objective: The objective of this study was to formulate an oral sustained release delivery system of ezetimibe mucoadhesive beads by ionic gelation technique based on sodium alginate used as a hydrophilic carrier in combination with carbopol 934P which acts as a rate modifier.Methods: Microbeads of ezetimibe were prepared using an easy method of ionotropic gelation by little modification while in addition of drug. The prepared beads were characterised for mean particle size, entrapment efficiency, swelling capacity, and in vitro release. They were also subjected to various studies such as Fourier Transform Infrared Spectrophotometer (FTIR) Spectroscopy for drug polymer reaction, Scanning Electron Microscopy for surface morphology, and Differential Scanning Calorimetric Analysis to determine the physical state of the drug in the beads.Results: The microspheres of ezetimibe were formulated successfully. The addition of drug concentration gives higher drug loading and higher conc. of Alcl+3 yields small diameter beads and lower drug entrapment. Analysis of the release profiles showed that the data corresponds to zero order release and the diffusion-controlled mechanism as suggested by Higuchi concept.Conclusion: It can be concluded that beads produced by the sequential method had higher drug entrapment. Beads produced by simultaneous yields larger beads in diameter. The concept was cleared that drug release was dependent upon the quantity of polymer and increase in conc. of. aluminium chloride retarded the drug release in the sequential method. Prepared beads enhance the dissolution of ezetimibe and the oral bioavailability and also reduce the fluctuations in the oral bioavailability.

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Sánchez-Amaya, J. M., Z. Boukha, M. R. Amaya-Vázquez, L. González-Rovira, and Francisco Javier Botana. "Analysis of the Laser Weldability under Conduction Regime of 2024, 5083, 6082 and 7075 Aluminium Alloys." Materials Science Forum 713 (February 2012): 7–12. http://dx.doi.org/10.4028/www.scientific.net/msf.713.7.

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Laser beam welding (LBW) show clear advantages compared with other techniques, as the low heat input, the high localization ability, the high welding speed, the high flexibility, the high weld quality and the high production rate. However, its applicability to aluminium alloys is limited, as they generally have high reflectivity, high thermal conductivity and low viscosity. In the present study, the laser weldability of four aluminium alloys (2024, 5083, 6082 and 7075) under conduction regime is analysed. High penetration butt welds could be obtained with a High Power Diode Laser (HPDL) under conduction regime. The properties of the weld beads such as the microstructure and microhardness were analysed. A linear function between the input laser fluence and the volume of melted material was obtained for the four alloys.

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Shabbar, Rana, Ali A. Al-Tameemi, and Athraa M. J. Alhassani. "The effect of expanded polystyrene beads (EPS) on the physical and mechanical properties of aerated concrete." Open Engineering 12, no. 1 (January 1, 2022): 424–30. http://dx.doi.org/10.1515/eng-2022-0020.

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Abstract There is a significant challenge to developing the strength and durability of the aerated concrete (AC) for structural applications, but to date, no researchers have focussed on the effect of expanded polystyrene beads (EPS) on the AC properties. EPS-AC consists of cement, sand, water and aluminium powder with commercially available spherical small, hollow and impermeable polystyrene beads. In this research, different contents of EPS from 0 to 4% by cement weight were added to create the AC with different densities. It is revealed that the greatest enhancements in the properties of EPS-AC were noticed when the EPS volume fraction was increased to 4%. The compressive, flexural strength and modulus of rupture were enhanced by 48, 37 and 125% respectively, whereas the density was raised slightly. Moreover, it was shown that all EPS-AC mixes could satisfy the requirements of structural lightweight concrete.

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Denizli, Adil, Ridvan Say, and Erhan Pişkin. "Removal of aluminium by Alizarin Yellow-attached magnetic poly(2-hydroxyethyl methacrylate) beads." Reactive and Functional Polymers 55, no. 1 (February 2003): 99–107. http://dx.doi.org/10.1016/s1381-5148(02)00219-5.

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Thenapakiam, Sathasivam, Devakumar Ganesh Kumar, Janarthanan Pushpamalar, and Muniyandy Saravanan. "Aluminium and radiation cross-linked carboxymethyl sago pulp beads for colon targeted delivery." Carbohydrate Polymers 94, no. 1 (April 2013): 356–63. http://dx.doi.org/10.1016/j.carbpol.2013.01.004.

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Votava, Jiří. "Using Welding for Renovations of Machine Parts Made of Aluminium Alloy." Acta Technologica Agriculturae 17, no. 4 (December 1, 2014): 91–95. http://dx.doi.org/10.2478/ata-2014-0021.

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Abstract Due to their mechanical characteristics, aluminium alloys are materials with high potential in the automotive industry. Thus, it is useful to analyse the weldability of individual alloys, not only for possible renovations of a machine part. This paper focuses on monitoring a welded metal made by the coated electrode OK 96.20. An alloy EN AW 5754 was used as a base welding material. This base material was used in two modifications. Firstly, samples degraded in oil at a temperature of 80 °C, and secondly, samples in their standard form without grease. In the experiment, the porosity of weld beads as well as tension characteristics were analysed. In order to identify the corrosion degradation of weldments, the test was performed in compliance with the norm ČSN EN ISO 9227.

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Yu, Peng, Ma Qian, Dacian Tomus, Craig A. Brice, Graham B. Schaffer, and Barry C. Muddle. "Electron Beam Processing of Aluminium Alloys." Materials Science Forum 618-619 (April 2009): 621–26. http://dx.doi.org/10.4028/www.scientific.net/msf.618-619.621.

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Electron beam (EB) direct manufacturing is an additive near-net shape digital fabrication process developed recently. The process offers a promising route for the fabrication of intricate speciality aluminium alloy parts for aircraft and aerospace applications because of the excellent energy coupling between an electron beam and aluminium. As part of a fundamental study on EB manufacturing of Al alloys, this work investigates the effect of the EB processing parameters on the development of the molten pool and the solidification characteristics of Al 2219 and Al 6061 alloys. The samples were processed using a 50kV electron beam gun over a wide range of beam currents (10-40mA) and welding speeds (0.3-0.86m/min) in both the static and oscillation focus modes. In the static focus mode, the molten pool is wedge-shaped; while in the oscillation focus mode, the molten pool is hemispherical, wider and shallower. In both cases, the depth and width of the molten pool increase with increasing beam current but they are less affected by the moving speed of the EB gun in the range 0.3-0.86m/min. Electron beam re-melted and subsequently re-solidified Al 2219 and Al 6061 alloys show microstructural features distinct from those obtained under sand casting and direct chill casting conditions. In particular, fine intermetallic precipitates in the size range 100-200nm are prominent in the equiaxed grains formed in the re-solidified weld beads of Al 6061 compared to the coarse intermetallic particles up to 10m in size prior to EB processing. EB processing offers opportunities for aluminium alloy development.

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Avettand-Fènoël, Marie Noëlle, Roland Taillard, Christophe Herbelot, and Abdellatif Imad. "Structure and Mechanical Properties of Friction Stirred Beads of 6082-T6 Al Alloy and Pure Copper." Materials Science Forum 638-642 (January 2010): 1209–14. http://dx.doi.org/10.4028/www.scientific.net/msf.638-642.1209.

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Friction stir welding (FSW) is a quite recent welding method which takes advantage of being performed in the solid state. Compared with the usual welding processes, it therefore presents many benefits such as a lower heat-input, a reduction of residual stresses and an elimination of the solidification defects etc.. Up to now, it has essentially been applied to aluminium alloys and far more recently to a small number of bimaterials. The present study deals with three kinds of beads between pure copper and a 6082 aluminium alloy. Both materials were butt joined by FSW. The welds differ by the location of the tool which was placed either at the interface between the two metals or on the copper or the 6082 side of this surface. Their structure was characterized at a multi-scale level by using a number of techniques. Tensile and microhardness tests were also performed. The tool place is shown to govern the microstructure and the ensuing mechanical behaviour of the weld. Its influence on the plastic flow with its repercussions on i) welding defects and ii) mechanical properties is going to be demonstrated. Some ways of improvement of the welding process will finally be suggested.

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Liu, L., J. L. Liu, X. L. Chen, and C. M. Jiao. "Synergistic effect between hollow glass beads and aluminium hydroxide in flame retardant EVA composites." Plastics, Rubber and Composites 43, no. 3 (January 14, 2014): 77–81. http://dx.doi.org/10.1179/1743289813y.0000000069.

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Kuo, Yu‐Ching, Souvik Pal, Fang‐Yu Li, and Chia‐Her Lin. "Polystyrene‐Supported Core–Shell Beads with Aluminium MOF Coating for Extraction of Organic Pollutants." Chemistry – An Asian Journal 14, no. 20 (July 29, 2019): 3675–81. http://dx.doi.org/10.1002/asia.201900737.

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Takahashi, K., S. Katayama, and A. Matsunawa. "Joint strength of weld beads produced in thin aluminium sheets by high-speed CO2laser welding." Welding International 17, no. 12 (December 2003): 934–38. http://dx.doi.org/10.1533/wint.2003.3200.

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Murambasvina, Gabriel, and Courtie Mahamadi. "Effective fluoride adsorption using water hyacinth beads doped with hydrous oxides of aluminium and iron." Groundwater for Sustainable Development 10 (April 2020): 100302. http://dx.doi.org/10.1016/j.gsd.2019.100302.

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Куракин, А. И., И. Г. Струков, Я. П. Скобликов, В. М. Карпов, and Е. И. Ефимов. "Prediction of bead layer geometry in P-GMAW wire arc additive manufacturing of aluminium alloys." MORSKIE INTELLEKTUAL`NYE TEHNOLOGII)</msg>, no. 2(60) (May 25, 2023): 245–52. http://dx.doi.org/10.37220/mit.2023.60.2.030.

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В работе представлено исследование влияния параметров импульсно-дуговой наплавки на геометрию наплавленного металла при актуальном сегодня проволочно-электродуговом выращивании (WAAM) из алюминиево-магниевых сплавов. В качестве варьируемых параметров импульсно-дугового процесса были выбраны скорость подачи электродной проволоки, скорость перемещения рабочего инструмента, размер капли. Геометрические параметры элементов оценивались путём измерения ширины и высоты слоя, а также определения припуска на последующую механическую обработку. Определены оптимальные режимы выращивания, характеризующиеся стабильным формированием одиночных валиков на подложке. Ширина и высота валика по всей длине изменялась незначительно. Установлено, что параметры импульсов тока влияют на качество сплавления слоев между собой и диаметр капли влияет на величину припуска для последующей механической обработки (критерий R). По результатам факторного эксперимента, получены регрессионные модели, которые могут использоваться для прогнозирования геометрических параметров слоя тонкостенного элемента, наплавленного с использованием технологии электродугового выращивания при изготовлении заготовок с учётом R-критерия. The paper presents a study of the influence of the parameters of pulsed arc surfacing on the geometry of the deposited metal in wire-arc additive manufacturing(WAAM) using aluminum-magnesium alloys. As variable parameters of the pulse-arc process, the wire feed speed, the working tool movement speed, and the drop size were chosen. The geometric parameters of the elements were evaluated by measuring the width and height of the layer, as well as determining the allowance for subsequent machining. The optimal growth regimes are determined, which are characterized by the stable formation of single beads on the substrate. The width and height of the bead along the entire length changed insignificantly. It has been established that the parameters of the current pulses affect the quality of the fusion of the layers to each other and the droplet diameter affects the allowance for subsequent machining (criterion R). Based on the results of the factorial experiment, regression models were obtained that can be used to predict the geometric parameters of the layer of a thin-walled element deposited using the technology WAAM, taking into account the R-criterion.

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Urbikain, Gorka, Jose M. Perez, Luis N. López de Lacalle, and Aritz Andueza. "Combination of friction drilling and form tapping processes on dissimilar materials for making nutless joints." Proceedings of the Institution of Mechanical Engineers, Part B: Journal of Engineering Manufacture 232, no. 6 (July 27, 2016): 1007–20. http://dx.doi.org/10.1177/0954405416661002.

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In this article, a new method for the rapid and economical production of ‘nutless’ bolted joins is presented, using a combination of two hole-making techniques, namely, form drilling and form tapping. The combined method achieves a quick way for the production of threaded holes on couples of dissimilar metal alloys, as it is the case of steels and aluminium alloys. After the simultaneous form drilling on the aluminium–steel pairs and followed by form tapping, a fastener can be introduced and screwed for achieving a tight bolted joint, without any necessity of nut. However, form drilling and threading are performed consecutively in the same machine tool, reducing the whole process time. The process parameters were studied for reducing the gap between surfaces and producing a good cup for making the posterior threading. Then, mechanical testing of several test pieces resulted in a similar behaviour than traditional bolted joints. Finally, corrosion tests were performed for a better understanding of the joint manufactured. In this way, savings in time and money are derived from the application of the approach. Target markets for the new approach are the light boilermaking industry in order to eliminate either welding beads or classical bolted joints using nuts.

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Jeyaseelan, Antonysamy, Ilango Aswin Kumar, Natrayasamy Viswanathan, and Mu Naushad. "Rationally designed and hierarchically structured functionalized aluminium organic frameworks incorporated chitosan hybrid beads for defluoridation of water." International Journal of Biological Macromolecules 207 (May 2022): 941–51. http://dx.doi.org/10.1016/j.ijbiomac.2022.03.129.

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Zaid, Hasnah Mohd, Noor Rasyada Ahmad Latiff, and Noorhana Yahya. "The Effect of Zinc Oxide and Aluminum Oxide Nanoparticles on Interfacial Tension and Viscosity of Nanofluids for Enhanced Oil Recovery." Advanced Materials Research 1024 (August 2014): 56–59. http://dx.doi.org/10.4028/www.scientific.net/amr.1024.56.

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Application of nanotechnology in enhanced oil recovery (EOR) has been increasing in the recent years. After secondary flooding, more than 60% of the original oil in place (OOIP) remains in the reservoir due to trapping of oil in the reservoir rock pores. One of the promising EOR methods is surfactant flooding, where substantial reduction in interfacial tension between oil and water could sufficiently displace oil from reservoir. The emulsion that is created between the two interfaces has a higher viscosity than its original components, providing more force to push the trapped oil. In this paper, the recovery mechanism of the enhanced oil recovery was determined by measuring oil-nanofluid interfacial tension and the viscosity of the nanofluid. Series of core flooding experiments were conducted using packed silica beads whichreplicate core rocks to evaluate the oil recovery efficiency of the nanofluid in comparison to that using an aqueous commercial surfactant, 0.3wt% sodium dodecyl sulfate (SDS). 117 % increase in the recovery of the residual oil in place (ROIP) was observed by the 2 pore volume (PV) injection of aluminium oxide nanofluid in comparison with 0.3wt% SDS. In comparison to the type of material, 5.12% more oil has been recovered by aluminium oxide compared to zinc oxide nanofluid in the presence of EM wave. The effect of the EM wave on the recoverywas also studied by and it was proven that electric field component of the EM waves has been stimulating the nanofluid to be more viscous by the increment of 54.2% in the oil recovery when aluminium oxide nanofluid was subjected to 50MHz EM waves irradiation.

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Akbari, Masoumeh, Shanmuganathan Gunalan, Nima Talebian, Benoit P. Gilbert, and Hong Guan. "Numerical study on the bearing behaviour and design of aluminium sub-heads with removable beads in façade systems." Journal of Building Engineering 43 (November 2021): 103149. http://dx.doi.org/10.1016/j.jobe.2021.103149.

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29

Kaliyaperumal, Viswanathan, Arul kumar Kandasamy, Vijayashanthi Ramalingam, Azhahianambi Palavesam, Dhinakarraj Gopal, and Raman Muthusamy. "Site-specific delivery of green tea coated aluminium magnesium silicate beads and studies on their effect against chicken coccidiosis." IET Nanobiotechnology 14, no. 9 (December 1, 2020): 750–55. http://dx.doi.org/10.1049/iet-nbt.2020.0043.

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30

Jagoo, S., Comondore Ravindran, and Dennis Nolan. "Fold Defects in Aluminum Alloy A356 Lost Foam Casting." Advanced Materials Research 15-17 (February 2006): 1–6. http://dx.doi.org/10.4028/www.scientific.net/amr.15-17.1.

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In the lost foam casting (LFC) of aluminum alloys, the expandable polystyrene (EPS) foam characteristics (foam composition, polymer processing and bead fusion) influence the formation of deleterious fold defects in the final casting. In this research, four types of EPS beads were investigated: (1) the regular EPS beads, (2) 2wt% hexabromocyclododecane and 2wt% dicumyl peroxide added to the EPS beads during the polymerization process, (3) 2wt% silicaalumina blended to EPS beads after the pre-expansion process of the beads and (4) 2wt% hexabromocyclododecane blended to EPS beads after the pre-expansion process of the beads. The density of the regular and modified EPS beads was kept constant at 25.63 kg/m3. Aluminum alloy A356 was poured at 1023 K into the window pattern. The window patterns with regular EPS beads did not fill completely and had identifiable carbon/oxide defects on the surface. The window patterns with the additives were completely filled with a few surface defects. From thermogravimetric analysis (TGA), it was found that the EPS beads with silica-alumina had a reduced onset temperature of degradation of EPS (from 634 K to 618 K) and a reduced activation energy (from 188 kJ/mol to 147 kJ/mol) relative to the regular beads. In the organic brominatedmodified EPS (both through blending and polymerization), it was found that the value of the preexponential (rate equation) was significantly increased. Through light optical microscopy (LOM) and scanning electron microscopy (SEM), it was found that the polymerization process additives increased the degree of bead fusion whereas the post pre-expansion additives decreased the degree of bead fusion. Finally, the EPS beads treated during the polymerization process produced castings with the least overall surface, subsurface and internal defects.

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31

Bek, Marko, Joamin Gonzalez-Gutierrez, Christian Kukla, Klementina Pušnik Črešnar, Boris Maroh, and Lidija Slemenik Perše. "Rheological Behaviour of Highly Filled Materials for Injection Moulding and Additive Manufacturing: Effect of Particle Material and Loading." Applied Sciences 10, no. 22 (November 11, 2020): 7993. http://dx.doi.org/10.3390/app10227993.

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Within this paper, we are dealing with a mixture of thermoplastic polymer that is filled with inorganic fillers at high concentrations up to 60 vol.%. A high number of particles in the compound can substantially change the rheological behaviour of the composite and can lead to problems during processing in the molten state. The rheological behaviour of highly filled materials is complex and influenced by many interrelated factors. In the present investigation, we considered four different spherical materials: steel, aluminium alloy, titanium alloy and glass. Particles with similar particle size distribution were mixed with a binder system at different filling grades (30–60 vol.%). We showed that the rheological behaviour of highly filled materials is significantly dependent on the chemical interactions between the filler and matrix material. Moreover, it was shown that the changes of the particle shape and size during processing lead to unexpected rheological behaviour of composite materials as it was observed in the composites filled with glass beads that broke at high contents during processing.

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32

Mazzaferro, J. A. E., and I. G. Machado. "Study of arc stability in underwater shielded metal arc welding at shallow depths." Proceedings of the Institution of Mechanical Engineers, Part C: Journal of Mechanical Engineering Science 223, no. 3 (December 1, 2008): 699–709. http://dx.doi.org/10.1243/09544062jmes1067.

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The main objective of this work was to study the effects of changes in hydrostatic pressure and electrode coating composition on the shielding metal arc behaviour during underwater wet welding. Thus, wet welding operations were performed by an automatic device using a hyperbaric chamber to simulate depths of 5.0, 12.5, and 20.0 m. A covered electrode already developed in W & RTL was used as reference and compared with others with different amounts of CaCO3, TiO2, and aluminium added to their coatings. Hence, effects of welding condition and electrode coating on weld metal were evaluated through visual inspection of the weld beads, measurement of porosity level, and the results related to welding current and voltage signals. The welding arc signals were analysed through indexes calculated from instantaneous values of current and voltage, and fast Fourier transforms frequency spectrum. The mixtures containing CaCO3 additions exhibit fewer defects, while those containing aluminium additions have presented a great amount of pores and other discontinuities in the weld metal. As expected, all consumables showed a higher deposition rate, as welds were performed at greater depths (pressures), confirming the effect of arc constriction and the consequent increase in current density. Moreover, a region of transition in the metal transfer mode was identified around a depth of 12.5 m, probably from short-circuit to globular. Also, a clear tendency of increase in arc stability for those welds performed at greater depths could be noticed, as well as better weld metal quality. On the other hand, those consumables with CaCO3 added to the coating exhibited the best arc stability for welds performed at shallow depths.

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Balasubramani, Ushadevi, Sangeetha Subramaniam, Liviu Mitu, and Vairam Sundararajan. "Batch and column studies on methylene blue using activated carbon/Al2O3 nano-composite and its impregnated calcium alginate beads." JOURNAL OF ADVANCES IN CHEMISTRY 12, no. 12 (December 20, 2016): 5599–612. http://dx.doi.org/10.24297/jac.v12i12.3890.

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Activated carbon/Al2O3 nano-composite (ANC) was synthesized by simple pyrolysis after incorporating the aluminium acetate precursor in activated carbon (AC) matrix. The as-synthesized composite was characterized by FT-IR, XRD, BET isotherm, SEM, EDX, and TEM. The size of Al2O3 nanoparticles in carbon matrix was found to be in the range of 10-35 nm. Adsorption characteristics of nano-composite was evaluated using methylene blue dye (MB) by batch and column studies. In batch process, the effect of concentration, temperature and pH were investigated. Batch adsorption study was interpreted with Langmuir, Freundlich, Temkin and Dubinin-Radushkevich (D-R) isotherms. Results showed that adsorption follows Freudlich isotherm model with an adsorption capacity of 116 mg/g at pH 7 at 30 Â°C and it increases with increase in pH. Kinetic data indicated that the adsorption of dye follows pseudo-second order kinetics model. The negative value of Î”G indicates the spontaneous nature of the adsorption process. For column study the nano-composite was fabricated into Calcium alginate beads (CAB). The performance of CAB was studied with different influent concentrations of MB, pH and bed depth and the results have been interpreted using Thomas and BDST models. The column shows an adsorption capacity of 285.57 mg/g of CAB at pH 7 with bed height of 10 cm and best fitted to BDST model. These outcomes indicate the capability of carbon/Al2O3 nano-composite for dye removal.

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Shen, Cheng, Yaqian Zhao, Ranbin Liu, Yi Mao, and David Morgan. "Adsorption of phosphorus with calcium alginate beads containing drinking water treatment residual." Water Science and Technology 78, no. 9 (November 15, 2018): 1980–89. http://dx.doi.org/10.2166/wst.2018.473.

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Abstract Aluminum-based drinking water treatment residuals (DWTR) were encapsulated by alginate to develop a pelletized media (DWTR-CA beads) for phosphorus (P) adsorption. The beads were successfully manufactured to uniform size and shape requirements. The effects of DWTR powder concentration and particle size, and bead mean size on P adsorption, were investigated. The DWTR was found to be an important component in the beads for P adsorption, while the calcium alginate shell contributed little for P adsorption. The maximum P adsorption capacity of the DWTR-CA bead was 19.42 mg P/g wet beads, corresponding to a bead diameter of 3.1 ± 0.2 mm and DWTR concentration of 2% (1% weight/volume (W/V)), mg/mL). The adsorption data fit well with the intra-particle diffusion model and the pseudo-second-order kinetic model, while both the Langmuir and Freundlich adsorption isotherms described the adsorption process well. Furthermore, the study on the effect of pH on P adsorption showed that acidic conditions resulted in a better P adsorption and the DWTR-CA beads have the function of pH neutralization. The findings of this study show that the DWTR-CA beads are a promising adsorbent/substrate for P removal.

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35

Giri, Tapan K., Deepak Verma, and Hemant R. Badwaik. "Effect of Aluminium Chloride Concentration on Diltiazem Hydrochloride Release from pH-sensitive Hydrogel Beads Composed of Hydrolyzed Grafted k-Carrageenan and Sodium Alginate." Current Chemical Biology 11, no. 1 (April 27, 2017): 44–49. http://dx.doi.org/10.2174/2212796810666161108152612.

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36

Adamiec, Janusz. "Repairing the WE43 Magnesium Cast Alloys." Solid State Phenomena 176 (June 2011): 99–106. http://dx.doi.org/10.4028/www.scientific.net/ssp.176.99.

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In addition to aluminium and titanium alloys, the magnesium alloys comprise the group of lightweight alloys which have the highest practical importance in structural applications. The WE43 alloy with the addition of rare earth elements and yttrium is used mainly for the sand mould castings for the aerospace industry. The castings for aerospace industry have complicated shapes and varying wall thickness, as a result of which they often have casting effects such as misruns, micro-shrinkages and cracks. The frequency of defect occurrence in the complicated shape casting may exceed 50%. The defects are repaired by means of welding and pad welding. Such practice is often used in foundries. The paper presents the results of repair evaluation of the WE43 alloy castings in the as-cast state by means of the TIG welding. The welding tests have been performed on the joints bevelled to “I”, “Y” and “V” and the technological repair guidelines have been formulated. The defect has been repaired and the non-destructive and structural tests have confirmed that the technology is correct. The WE43 alloy should be welded and pad welded with maximum linear arc energy of 3.0 kJ/cm, straight beads, with filler metal of a similar chemical composition, in the as-delivered state.

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Müller, Miroslav, and Petr Valášek. "Impact Strength of Filled Polymer Materials." Materials Science Forum 883 (January 2017): 46–50. http://dx.doi.org/10.4028/www.scientific.net/msf.883.46.

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Polymers rank among a significant group of technical materials. One of requirements for this constructional material is to have enough resistance to a dynamic loading. Especially in the area of connecting the materials reactoplastics are used, which are distinguished for a low resistance to the dynamic loading. One solution for increasing an impact strength is filling the reactoplastics, i.e. a formation of polymer composites. The aim of the research was to evaluate an impact strength of various polymer materials (composites filled with different types of a filler, structural two-component epoxies, mixed recycled plastics, PPO – polyphenyle oxide and PS – polystyrene). The Dynstat method CSN 64 0611 was chosen for the evaluation of the impact strength. Reactoplastics matrix on the basis of two-component epoxy adhesive with high liquidity and an increased speed of a hardening GER reaches low values of the impact strength (2.54 ± 0.30 kJ·m-2). It is evident from the experimental results the positive effect of aluminium microparticles GER MFAI (3.26 ± 0.35 kJ·m-2), glass beads GR B134 (2.83 ± 0.29 kJ·m-2) and microfibres of polyamide from the process of tyre recovery GER MPA (3.92 ± 0.25 kJ·m-2) on the impact strength. The results of this experiments show the possibility of the modification of the relative fragile epoxy resin with the filler, which increases the impact strength.

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38

Dlamini, Caroline Lomalungelo, Lueta-Ann De Kock, Kebede Keterew Kefeni, Bhekie Brilliance Mamba, and Titus Alfred Makudali Msagati. "Novel hybrid metal loaded chelating resins for removal of toxic metals from acid mine drainage." Water Science and Technology 81, no. 12 (June 12, 2020): 2568–84. http://dx.doi.org/10.2166/wst.2020.285.

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Abstract Iron (Fe), zirconium (Zr) and titanium (Ti) oxides nanoparticles were each embedded onto a weak acid chelating resin for support using the precipitation method to generate three hybrid adsorbents of hydrated Fe oxide (HFO-P), hydrated Zr oxide (HZO-P) and hydrated Ti oxide (HTO-P). This paper reports on the characterization, performance and potential of these generated nanoadsorbents in the removal of toxic metal ions from acid mine drainage (AMD). The optimum contact time, adsorbent dose and pH for aluminium (Al) (III) adsorption were established using the batch equilibrium technique. The metal levels were measured using inductively coupled plasma-optical emission spectrometry. The scanning electron microscopy–energy dispersive X-ray spectroscopy results confirmed the presence of the metal oxides within the hybrid resin beads. HFO-P, HZO-P and HTO-P adsorbed Al(III) rapidly from synthetic water with maximum adsorption capacities of 54.04, 58.36 and 40.10 mg/g, respectively, at initial pH 1.80 ± 0.02. The adsorption of Al(III) is of the second-order in nature (R2 > 0.98). The nanosorbents removed ten selected metals from environmental AMD and the metal removal efficiency was in the order HTO-P > HZO-P > HFO-P. All three hybrid nanosorbents can be used to remove metals from AMD; the choice would be dependent on the pH of the water to be treated.

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Biftu, Wondwosen Kebede, Suneetha Mekala, and Kunta Ravindhranath. "De‐fluoridation of Polluted Water Using Aluminium Alginate Beads Doped with Green Synthesized ‘Nano SiO 2 +Nano CeO 2 ‐ZrO 2 ’, as an Effective Adsorbent." ChemistrySelect 5, no. 47 (December 17, 2020): 15061–74. http://dx.doi.org/10.1002/slct.202003744.

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40

Morais, Paulo J., Bianca Gomes, Pedro Santos, Manuel Gomes, Rudolf Gradinger, Martin Schnall, Salar Bozorgi, et al. "Characterisation of a High-Performance Al–Zn–Mg–Cu Alloy Designed for Wire Arc Additive Manufacturing." Materials 13, no. 7 (April 1, 2020): 1610. http://dx.doi.org/10.3390/ma13071610.

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Ever-increasing demands of industrial manufacturing regarding mechanical properties require the development of novel alloys designed towards the respective manufacturing process. Here, we consider wire arc additive manufacturing. To this end, Al alloys with additions of Zn, Mg and Cu have been designed considering the requirements of good mechanical properties and limited hot cracking susceptibility. The samples were produced using the cold metal transfer pulse advanced (CMT-PADV) technique, known for its ability to produce lower porosity parts with smaller grain size. After material simulations to determine the optimal heat treatment, the samples were solution heat treated, quenched and aged to enhance their mechanical performance. Chemical analysis, mechanical properties and microstructure evolution were evaluated using optical light microscopy, scanning electron microscopy, energy dispersive X-ray spectroscopy, X-ray fluorescence analysis and X-ray radiography, as well as tensile, fatigue and hardness tests. The objective of this research was to evaluate in detail the mechanical properties and microstructure of the newly designed high-performance Al–Zn-based alloy before and after ageing heat treatment. The only defects found in the parts built under optimised conditions were small dispersed porosities, without any visible cracks or lack of fusion. Furthermore, the mechanical properties are superior to those of commercial 7xxx alloys and remarkably independent of the testing direction (parallel or perpendicular to the deposit beads). The presented analyses are very promising regarding additive manufacturing of high-strength aluminium alloys.

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Pham, Ngoc Hieu. "Elastic Global Buckling Moments of Cold-rolled Aluminium Alloy Asymmetric Section Beams." E3S Web of Conferences 410 (2023): 03004. http://dx.doi.org/10.1051/e3sconf/202341003004.

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Cold-rolled aluminium sections are the new products introduced by BlueScope Permalite. These products have illustrated their cost-effectiveness in comparison with the traditional extruded aluminium alloy sections, which has attracted the attention of users and researchers. Research projects on cold-rolled aluminium alloy structures have been carried out to investigate the strengths and behaviors of such members that are the base for the development of the design guidelines for this new structural type. Cold-rolled aluminum alloy sections in the form of thin-walled sections are sensitive to instability. The design guidelines, therefore, have been proposed on the basis of the design of cold-formed steel structures with the development of the Direct Strength Method. The buckling analyses are conducted to determine the elastic buckling load, which is a compulsory step for the application of this method. The buckling analyses for symmetrical sections have been thoroughly investigated whereas these analyses for asymmetric sections are not clearly regulated in the design standards. Based on the experimental and numerical investigations on cold-rolled aluminium asymmetric section beams in a research project conducted at the University of Sydney, the paper will investigate the elastic global buckling moments of these asymmetric beams by using different methods including numerical, experimental and theoretical methods. The investigated results are subsequently discussed to figure out the procedure for the determination of elastic global buckling moments of the investigated cold-rolled aluminium alloy asymmetric section beams.

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Matsuura, Kiyotaka, Naoki Mizuta, Soshu Kirihara, Yoshinari Miyamoto, and Atsushi Yumoto. "Intermetallic Coating Using a 3-Dimensional Micro Welder." Materials Science Forum 631-632 (October 2009): 259–64. http://dx.doi.org/10.4028/www.scientific.net/msf.631-632.259.

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The authors have studied a new method of intermetallic coating using a small TIG welder. This method is based on a reaction between small liquid beads produced from very thin metal wire and the substrate metal surface. The authors designed a computer-aided 3-dimensional micro welder (3DMW) for a previous study on freeform fabrication of intermetallics, and have applied it to this study on intermetallic coating. In this study, a predetermined length of thin aluminum wire was fed onto the titanium substrate surface, and a spark was stricken from a thin electrode of a W-Ce2O3 alloy to make a small aluminum liquid bead on the titanium substrate surface and to simultaneously melt a small area of the substrate surface beneath the liquid bead. All process conditions had been programmed beforehand, including the length of the wire feeding per spark, the position of the electrode, electric power, movement of the stage holding the substrate, etc. The liquid bead containing aluminum and titanium rapidly solidified on the titanium substrate surface producing titanium aluminides on it. Repetition of the aluminum wire feeding, the electrode positioning and the spark striking produced a coating layer consisting of sub-layers of TiAl3, TiAl and Ti3Al from the surface side to the substrate side. Vickers hardness and wear resistance of the coated sample were remarkably improved.

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HANSEN, JIM, and DENNIS D. HARWIG. "Impact of Electrode Rotation on Aluminum GMAW Bead Shape." Welding Journal 102, no. 6 (June 1, 2023): 125–36. http://dx.doi.org/10.29391/2023.102.010.

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Aluminum gas metal arc welding (GMAW) uses inert shielding gas to minimize weld pool oxidation and reduce susceptibility to porosity and incomplete fusion defects. For aluminum shipbuilding, naval welding requirements highly recommend the use of helium-argon mixtures or pure helium shielding gas to provide a broader heat field and better weld toe fusion. Pure argon shielding gas can be used but has been susceptible to incomplete fusion and porosity defects, where argon’s lower thermal conductivity promotes a narrower arc heat field and shallow weld fusion depth. Using helium is a concern because it is a finite resource that costs approximately five times more than argon. The rotating electrode pulsed GMAW process was investigated to improve argon shielding fusion characteristics and reduce helium usage. Argon-shielded bead-on-plate tests were used to evaluate the relationship between ER5183 electrode rotation parameters and arc power on constant deposit area bead shape. These tests were compared to stringer beads (no oscillation) that were made with argon, helium, and helium-argon shielding gases. Electrode rotation improved underbead fusion depth width and toe fusion. With preferred rotation parameters, the bead width and incomplete fusion at weld toes were equivalent to helium-based welds. For weld reinforcement, electrode rotation promoted a nonsymmetric profile with deposit bias on the bead side, where rotation direction was aligned with travel direction. The bead-side deposit bias is an advantage based on preliminary horizontal V-groove welding procedures using ceramic backing. Electrode rotation can offset the effects of gravity, promoting a smoother bead and fusion profile.

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Zhang, Zheng, Jin Ping Zhuang, Xue Chao Chen, and Zhi Bin Wang. "Analysis on In-Plane Seismic Performance of Aluminium Beams under Cyclic Bending." Advanced Materials Research 1049-1050 (October 2014): 365–68. http://dx.doi.org/10.4028/www.scientific.net/amr.1049-1050.365.

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The in-plane mechanical properties of aluminium beams under cyclic bending were analyzed and contrasted to those of steel beams. In order to carry out research on in-plane seismic performance of aluminium beams, a finite element analysis method was presented. The method was based on general FEA software, ANSYS. The analysis method considered the effects of material nonlinearity and geometrical nonlinearity. On this basis, hysteretic curves and reversal skeleton curves of 6061-T6 aluminium beams, 6061-T4 aluminium beams and Q235 steel beams under cyclic bending were get and contrasted. The analysis shows that the in-plane seismic performance of the aluminium beams is similar with the low carbon steel beams and is notably influenced by material properties.

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Tshai, Kim Yeow, Mei Hua Chin, Siew Shee Lim, Hwei San Loh, Ernest Hsin Nam Yong, and Tamrin Nuge. "Fish Scale Collagen Functionalized Thermo-Responsive Nanofibres." Key Engineering Materials 846 (June 2020): 189–94. http://dx.doi.org/10.4028/www.scientific.net/kem.846.189.

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Smart thermosensitive polymer such as poly (N-isopropyl acrylamide) (PNIPAM) and dominant fibrous protein of connective tissue such as collagen (CLG) possess great potential in biomedical and tissue engineering applications. The objectives of current work aim to explore potential of PNIPAM and collagen by (i) establish a stable procedure to extract collagen from fresh water Tilapia fish scale (TFS) and (ii) fabricate PNIPAM and hybrid PNIPAM-CLG nanofibrous scaffolds through electrospinning technique and investigate their material-process-structure behaviour. Type I collagen was derived through acid hydrolysis of TFS. Electrospinning of PNIPAM was carried out with 16, 18 and 20 wt% PNIPAM concentration in methanol (MeOH) while PNIPAM-CLG was prepared through blending measured quantity of PNIPAM dissolved in water with collagen dissolved in acetic acid. Material properties, viscosity, morphology and thermo-physical behaviors of the derived collagen, electrospun PNIPAM and PNIPAM-CLG scaffolds were characterized. Results from SDS-PAGE and FTIR confirmed that the isolated TFS collagen is of type I. EDX revealed that demineralization eliminated the aluminium, magnesium, silicon and phosphorus while significantly reduced the sulfur elements from raw TFS. SEM observation of the collagen morphology shown a fluffy and fibrillary lamellae structure. Electrospun scaffolds were successfully fabricated with 16 and 18 wt% PNIPAM in MeOH. Both homogeneity and average fibre diameter (Davg) were greater in the 18 wt% PNIPAM scaffold, in which the Davg for 16 and 18 wt% were ~110 and ~131.7 nm respectively. However, PNIPAM at 20 wt% failed to be electrospun owing to its excessively high viscosity. On the other hand, SEM observation revealed that the electrospun hybrid PNIPAM-CLG scaffold has Davg of ~105.5 nm amid the presence of numerous elongated beads.

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Zhang, Zhao Dong, and Xiang Yu Kong. "Study on DC Double Pulse MIG Welding of Automobile Aluminum Alloy." Advanced Materials Research 295-297 (July 2011): 1933–37. http://dx.doi.org/10.4028/www.scientific.net/amr.295-297.1933.

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In this paper, the features of weld formation, porosity, arc behavior, microstructure and mechanical properties of 6061 Al alloy thin sheet welds by direct current (DC) double pulse metal inert gas (MIG) welding process are investigated and compared with the traditional DC MIG welding process. Results show that continuous one-side welding with back forming weld beads without spatters, undercuts or cracks can be obtained by using the DC double pulse MIG welding process. The porosity of weld bead can be largely reduced by using the process. The arc of DC double pulse MIG welding is stable without arc blowout, and the metal transfer model of DC double pulse MIG welding is better than that of DC MIG welding. Microstructure of the weld bead by DC double pulse MIG welding shows a dendrite structure and it is fine and uniform. The average ultimate tensile strength and elongation of the weld bead by DC double pulse MIG welding can get to 228MPa, 80% of base metal, and 7.6%, 63% of base metal.

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Zhang, Zheng, Xue Chao Chen, Yong Chao Ma, and Zhi Bin Wang. "Analysis on Out-of-Plane Seismic Stability Performance of Aluminium Beams under Cyclic Bending." Advanced Materials Research 1049-1050 (October 2014): 369–73. http://dx.doi.org/10.4028/www.scientific.net/amr.1049-1050.369.

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The out-of-plane mechanical properties of aluminium beams under cyclic bending were studied and contrasted to those of steel beams. In order to carry out research on out-of-plane seismic stability performance of aluminium beams, a method by finite element analysis was proposed. The method was based on FEA software, ANSYS. The analysis methods considered the effects of material nonlinearity, geometrical nonlinearity and initial imperfection. Based on above, hysteretic curves, reversal skeleton curves and stiffness degradation curves of 6061-T6 aluminium beams, 6061-T4 aluminium beams and Q235 steel beams under cyclic bending were get and contrasted. Results show that the out-of-plane seismic stability performance of the aluminium beams is lower than the low carbon steel beams and is significantly influenced by material properties.

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48

Jana, Animesh, Omkar Roy, Shanmuk Srinivas Ravuru, and Sirshendu De. "Tuning of graphene oxide intercalation in magnesium aluminium layered double hydroxide and their immobilization in polyacrylonitrile beads by single step mussel inspired phase inversion: A super adsorbent for lead." Chemical Engineering Journal 391 (July 2020): 123587. http://dx.doi.org/10.1016/j.cej.2019.123587.

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Chybiński, Marcin, and Łukasz Polus. "Structural Behaviour of Aluminium–Timber Composite Beams with Partial Shear Connections." Applied Sciences 13, no. 3 (January 27, 2023): 1603. http://dx.doi.org/10.3390/app13031603.

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In this paper, the short-term behaviour of innovative aluminium–timber composite beams was investigated. Laminated veneer lumber panels were attached to aluminium beams with screws. Recently conducted theoretical, experimental, and numerical investigations have focused on aluminium–timber composite beams with almost full shear connections. However, no experiments on aluminium–timber composite beams with partial shear connections have yet been conducted. For this reason, composite action in composite beams with different screw spacing was studied in this paper. Four-point bending tests were performed on aluminium–timber composite beams with different screw spacing to study their structural behaviour (ultimate load, mode of failure, load versus deflection response, load versus slip response, and short-term stiffness). The method used for steel–concrete composite beams with partial shear connection was adopted to estimate the load bearing capacity of the investigated aluminium–timber composite beams. The resistance to sagging bending of the aluminium–timber composite beams with partial shear connections from the theoretical analyses differed by 6–16% from the resistance in the laboratory tests. In addition, four 2D numerical models of the composite beams were developed. One model reflected the behaviour of the composite beam with full shear connection. The remaining models represented the composite beams with partial shear connections and were verified against the laboratory test results. Laminated veneer lumber was modelled as an orthotropic material and its failure was captured using the Hashin damage model. The resistance to sagging bending of the aluminium–timber composite beams with partial shear connections from the numerical analyses were only 3–6% lower than the one from the experiments.

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Liu, Xiao, Xiaoyan Yu, and Jiaxiang Xue. "Effect of Double-Pulse Characteristics on Weld Bead Formation and Mechanical Properties in Metal Inert Gas Welding." Metals 11, no. 6 (June 21, 2021): 995. http://dx.doi.org/10.3390/met11060995.

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Aluminum alloy has been widely used due to its excellent workability, and double-pulse metal inert gas welding (MIG) has become a popular technique in aluminum alloy welding. In this study, a cross-complementary test was performed to study the effect of double-pulse characteristics on weld bead formation and mechanical properties in MIG welding. The test was carried out on an AA6061 aluminum alloy using flat overlaying welding. After welding, the micro-metallographic structure and macro-mechanical performance of the weld bead were explored. The test results showed that the two methods of increasing the base current amplitude or the low-frequency of the current effectively enhanced the oscillation of the molten pool, refined the grain size of the fusion zone, and improved the mechanical properties of the weld. Additionally, by comparing the macroscopic photograph of the specimen and the corresponding welding parameters in the test, the formation characteristics of the bead’s fish-scale pattern in double-pulse MIG welding were found when appropriate welding parameters were adopted and weld bead formation was good. This test result provides a strong scientific basis for the selection of welding parameters in the actual promotion and application of double-pulse MIG welding.

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Journal articles on the topic 'Aluminium Beads'

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