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AA7075 is one of the most important structural materials extensively used in automobile and aerospace industries. Extensive research on its formability aspects is required to develop useful components of complex shapes out of this material. One of the ways to measure the formability is to find its deep drawability characteristics. In this study, the significance of three important deep drawing process parameters namely blank temperature, die arc radius and punch velocity on the deep drawing characteristics of aluminium 7075 sheet was determined. The combination of finite element method and Taguchi analysis was used to determine the influence of process parameters. Simulations were carried out as per orthogonal array using DEFORM 2D software. Based on the predicted deformation of deep drawn cup and analysis of variance test (Anova), it was observed that blank temperature has greatest influence on the formability of aluminium material followed by punch velocity and die arc radius. Multiple regression analysis techniques were applied in modelling the behaviour of AA 7075 aluminium alloy under multistep deformation conditions.

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Friction Stir Processing AZ31B Mg Alloy Grain Refinement Taguchi In this investigation, the effect of friction stir processing (FSP) parameters such as rotational speed, traverse speed and tool tilt angle on the mechanical properties of tensile strength, hardness and impact energy of magnesium alloy AZ31B was studied. The experiments were carried out as per Taguchi parametric design concepts and an L9 orthogonal array was used to study the influence of various combinations of process parameters. Statistical optimization technique, ANOVA was used to determine the optimum levels and to find the significance of each process parameter. The results indicate that rotational speed (RS), and traverse speed (TS) are the most significant factors, followed by tilt angle (TA) in deciding the mechanical properties of friction stir processed magnesium alloy. In addition, mathematical models were developed to establish relationship between different process variables and mechanical properties.

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A facile synthesis of homoallylic alcohols is achieved by the allylation of aldehydes with allylic metal reagents or allyl halides using copper fluor-A C H T U N G T R E N N U N G apatite (CuFAP) as catalyst under mild reaction conditions. A variety of aldehydes were converted to the corresponding homoallylic alchohols, demonstrating the versatility of the reaction.

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