Finite Element Analysis and Optimization of Equal-Channel Angular Rolling Process by Using Taguchi Methodology

As a severe plastic deformation process, equal-channel angular rolling (ECAR), which is based on equal-channel angular pressing (ECAP), can be used to develop fine-grain materials. With this in mind, in this study, the strain behavior of commercial AA-6061 aluminum alloy during the ECAR was investigated. Taguchi methodology and variance analysis were used to examine the effect of die channel angles, angular speed, and friction coefficient influence on the effective strain (ES) and standard deviation (SD) of the effective strain of ECAR. In this regard, the finite element method was exercised to determine the optimum parameters for ECAR processing to enhance the strain behavior. The results revealed that decreasing the die channel angles and increasing angular speed and friction coefficient result in better ES with 56, 23, and 17 percent effects, respectively. Based on the simulation results, the AA-6061 was exposed to the ECAR process with a low die angle, high angular speed, and no lubricant state. The microstructure results demonstrated significant grain size changes through the ECAR process, resulting in the decrease in grain size from 70 up to 20 µm.