Optimization of ECMAP Parameters in the Production of Ultra-Fine Grained Al1050 Strips Using Grey Relational Analysis

Production of lightweight metals with a higher strength to weight ratio is always the main goal of researchers. In this article, the equal channel multi angular pressing (ECMAP) process as one of the most appealing severe plastic deformation (SPD) methods for production of ultra-fine grained (UFG) materials is studied. Two main routes A and C were investigated by finite element method (FEM) and compared with each other from different perspectives. ABAQUS commercial software was used to evaluate the maximum strain, maximum required force, and strain inhomogeneity index in both routes and the obtained FEM results were verified by both theoretical calculations and experimental tests. It is inferred that although equivalent plastic strain (PEEQ) in route A is higher than that in route C, the strain homogeneity as a quality factor for route C is higher. So, route C was selected for more investigation and optimization. Grey relational analysis was used as the optimization method. Geometrical parameters were taken as input variables and both inhomogeneity index and maximum required load were taken as objectives. Then, the suggested tests by full factorial method were simulated by FEM. After optimization, it was concluded that the best set up belongs to experiment number 20 in which the values of Φ1, ψ1 and ψ2 are 165°, 0° and 15°, respectively. Also, it was inferred that among geometrical parameters, die channel angle (Φ1) is the most effective parameter.