An algorithm for prediction of die geometry effects on strength behavior of sheets fabricated by groove pressing process

In this paper, the constrained groove pressing (CGP) process of Al 5052 sheets are experimentally and numerically studied. The CGP process produces the micro-grained-size sheets to enriched strength nano-grained-size ones. The goal of this investigation is the development of an algorithm for the mechanical behavior (Strength and Hardness) prediction of the sheets fabricated by the process. The algorithm enables one to evaluate the die geometry and pressing pass definition effects on mechanical behavior of the fabricated sheet. The proposed algorithm is based on the available relation in literature between the macroscopic behavior and the grain size in metal sheets and between the hardness and the strength properties of metal sheets. The Al 5052 samples are fabricated by two passes of the CGP process. The yield strength and the Vickers hardness of the annealed, the one and two pass CGPed samples are experimentally obtained. The predicted results by the developed algorithm are in good agreement with the experimental data. The comparison of the predicted results by the algorithm with available experimental data for the mechanical behavior of the CGPed pure aluminum sheets with different dies reveals the good accuracy of the proposed algorithm. The algorithm enables one to economical save from the time-consuming experimental evaluation of groove geometry effects on the fabricated sheets and optimum die selection. The effects of the die groove angle on the yield strength and the hardness of the CGPed Al 5052 sheets are estimated using the developed algorithm.