Document Type : Original Article


Faculty of Mechanical Engineering, Urmia University of Technology, Urmia, Iran


Equal channel angular pressing (ECAP) is one of the most appealing severe plastic deformation (SPD) methods. The proposed equal channel multi angular pressing (ECMAP) process enhances the efficiency of traditional ECAP technique with decreasing the process time. In this study, a complete investigation was done by the design of experiment (DOE) by compound Taguchi-Grey technique. FEM was applied by ABAQUS software in order to achieve responses of proposed Taguchi tests. Die geometrical parameters together with an important process parameter were selected as input factors and strain characteristics and also, required process load were selected as responses. The relationships between responses and input factors were obtained by regression analysis. Then, an analysis of variance (ANOVA) was used to determine the influence of each input factor on responses. ANOVA analysis revealed that FC with contribution percentage of 87.21% has the most influential factor on RPL. Furthermore, it was inferred that among input factors, with contribution percentage of 94.57% has the most effect on the PEEQ. Finally, a multi objective optimization study was done by grey relational analysis. It was concluded that among all input factors, die channel angle, friction coefficient (FC), and die corner angle with contribution percentages of 42.30%, 26.08% and 14.84% are the first, second and third most influential factors on objectives, respectively.


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