Education and Application of Upper Bound Theorem in Cold Rolling of Tri-Layer Srip

In this paper, A mathematical model for cold rolling of symmetrical tri-layer strip is proposed using the upper bound theorem to investigate the plastic deformation behavior of the strip at the roll gap. With implementation steps to express in order to analysis of cold rolling process, can calculate and forecast the rolling power, rolling force, average pressure between layers and thickness reduction of each layer. In order to validity the theoretical model ,experiments on sandwich strip rolling are conducted by employing aluminum, mild steel (Al/St/Al)as the layers of the sandwich strips and results is compared together. It is found that all of theoretical predictions are in good agreement with the experimental measurements