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This paper aims to investigate the corrosion behavior of AZ31 alloy as a prospective biomedical implant in two different simulated biological solutions and various immersion times.

Results of electrochemical experiments indicated that corrosion resistance of specimens immersed for 24 h was superior, suggesting that the surface layer is capable of protecting alloy.

Scanning electron micrographs revealed that this layer abounds with cracks, exhibiting optimum quality in 24 h immersion time, after which it begins to develop corrosion pits. Energy dispersive spectroscopy analysis suggested that the layer is mainly composed of magnesium hydroxide with precipitates of P and Ca containing species present on its surface, which is an indication of biocompatibility.

Finally, corrosion performance of Mg alloy was found to be slightly better in Lac-simulated biological solution (SBF) solution, which is more representative of actual physiological environment as compared to conventional SBF solutions.

Mg-Al powder mixture was used to manufacture Mg-Al alloy by laser powder bed fusion (LPBF) process. This study aims to investigate the influence of initial Al content and processing parameters on the formability, microstructure and consequent mechanical properties of the laser powder bed fused (LPBFed) component.

In this study, Al powder with different weight ratio ranged from 3 to 9 per cent was mixed with pure Mg powder, and the powder mixture was processed using different LPBF parameters. Microstructure and compressive properties of the LPBFed components were examined.

It was found that the presence of Al significantly modified the microstructure and improved the mechanical properties of the LPBFed components. Higher volume of ß-Al12Mg17 precipitates was produced at higher initial Al content and higher laser energy density. For this reason, the a-Mg was significantly refined and the compressive strength was improved. The highest yield compressive strength achieved was 279 MPa when using Mg-9 Wt. % Al mixture.

This work demonstrates that LPBF of Mg-Al powder mixture was a viable way to additively manufacture Mg-Al alloy. Both Al content and processing parameters can be modified to control the microstructure and mechanical properties of the LPBFed components.

The main purpose of the present work is to evaluate, the microstructural and mechanical properties of friction stir welded plates of AZ91D magnesium alloy with 3 mm thickness, and to determine the optimum range of welding conditions.

Microstructure and fractographic studies were carried out using scanning electron microscopy (SEM). Vickers micro hardness test was performed to evaluate the hardness profile in the region of the weld area. The phases in the material were confirmed by X-Ray diffraction (XRD) analysis. Transverse tensile tests were conducted using universal testing machine (UTM) to examine the joint strength of the weldments at different parameters.

Metallographic studies revealed that each zone shown different lineaments depending on the mechanical and thermal conditions. Significant improvement in the hardness was observed between the base material and weldments. Transverse tensile test results of weldments had shown almost similar strength that of base material regardless of welding speed. Fractographic examination indicated that the welded specimens failed due to brittle mode fracture. Through these studies it was confirmed that friction stir welding (FSW) can be used for the welding of AZ91D magnesium alloy.

In the present study, the welding speed varied from 25 mm/min to 75 mm/min, tilt angle varied from 1.5^° to 2.5^° and constant rotational speed of 500 rpm.

Magnesium and aluminum based alloys which are having high strength and low density, used in automotive and aerospace applications can be successfully joined using FSW technique. The fusion welding defects can be eliminated by adopting this technique.

Limited work had been carried out on the FSW of magnesium based alloys over aluminum based alloys. Furthermore, this paper analyses the influence of welding parameters over the microstructural and mechanical properties.

This paper gives a review of the finite element techniques (FE) applied in the area of material processing. The latest trends in metal forming, non‐metal forming, powder metallurgy and composite material processing are briefly discussed. The range of applications of finite elements on these subjects is extremely wide and cannot be presented in a single paper; therefore the aim of the paper is to give FE researchers/users only an encyclopaedic view of the different possibilities that exist today in the various fields mentioned above. An appendix included at the end of the paper presents a bibliography on finite element applications in material processing for 1994‐1996, where 1,370 references are listed. This bibliography is an updating of the paper written by Brannberg and Mackerle which has been published in Engineering Computations, Vol. 11 No. 5, 1994, pp. 413‐55.

This study aims to investigate the role of aluminium (Al) in marine environment and the corrosion mechanism of galvalume coatings by conducting accelerated experiments and data analysis.

Samples were subjected to accelerated corrosion for 136 days via salt spray tests to simulate the natural conditions of marine environment and consequently accelerate the experiments. Subsequently, the samples were examined using various test methods, such as EDS, scanning electron microscopy (SEM), X-ray diffraction (XRD) and electrochemical impedance spectroscopy (EIS), and the obtained data were analysed.

Galvalume coatings comprised interdigitated zinc (Zn)-rich and dendritic Al-rich phases. Corrosion was observed to begin with a Zn-rich phase. The primary components of the corrosion product film were Al₂O₃ and Zn₅(OH)₈Cl₂·H₂O. It was confirmed that the role of Al was to form a dense protective film, thereby successfully blocking the entry of corrosive media and protecting the iron substrate.

This study provides a clearer understanding of the corrosion mechanism and kinetics of galvalume coatings in a simulated marine environment. In addition, the role of Al, which is rarely mentioned in the literature, was investigated.

The purpose of this paper is to demonstrate the preliminary work on using laser cladding technology for the restoration of structural integrity.

The primary methodology used in this research is to develop a laser cladding‐based metal deposition technique to articulate restoration of structural geometry affected by corrosion damages. Following from this method, it is planned to undertake further work to use the laser cladding process to restore geometry and the associated static/fatigue strength.

This work has found that it is possible to use laser cladding as a repair technology to improve structural integrity in aluminium alloy aircraft structures in terms of corrosion reduction and geometrical restoration. Initial results have indicated a reduction of static and fatigue resistance with respect to substrate. But more recent works (yet to be published) have revealed improved fatigue strength as measured in comparison to the substrate structural properties.

The research is based on an acceptable materials processing technique.

TDS Circuits plc, the Blackburn based high‐technology manufacturer of multilayer printed circuit boards, has made two new senior management appointments. John W. Whybrow has been appointed Managing Director, and David Dickson becomes the new Sales and Marketing Manager.

Life‐cycle analysis (LCA) provides a general framework for assessing and summarizing all of the information important to a decision. LCA has been used to analyze the desirability of replacing lead (Pb) with a composite of tungsten (W) and tin (Sn) in projectile slugs used in small arms ammunition at US Department of Energy (DOE) training facilities for security personnel. The analysis includes consideration of costs, performance, environmental and human health impacts, availability of raw materials, and stakeholder acceptance. Projectiles developed by researchers at Oak Ridge National Laboratory (ORNL) using a composite of tungsten and tin are shown to perform as well as, or better than, those fabricated using lead. A cost analysis shows that tungsten‐tin is less costly to use than lead, since, for the current number of rounds used annually, the higher tungsten‐tin purchase price is small compared with higher maintenance costs associated with lead. The tungsten‐tin composite presents a much smaller potential for adverse human health and environmental impacts than lead. Only a small fraction of the world’s tungsten production occurs in the USA, however, and market‐economy countries account for only around 15 per cent of world tungsten production. Concludes that stakeholders would prefer tungsten‐tin on the basis of total cost, performance, reduced environmental impact and lower human toxicity. However, lead is preferable on the basis of material availability. Life cycle analysis clearly shows that advantages outweigh disadvantages in replacing lead with tungsten‐tin in small‐caliber projectiles at DOE training facilities. Concerns about the availability of raw tungsten are mitigated by the ease of converting back to lead (if necessary) and the recyclability of tungsten‐tin rounds.