New Theoretical Calculation of Limit Drawing Ratio by Taking into Account Material Parameters Changes during Deep Drawing of Cylindrical Cup

摘要

One of the most important, yet simplest deep-drawing operations on a flat blank of sheet metal is the production of a cylindrical cup. Optimization of process parameters in sheet metal forming is an important task to reduce manufacturing cost. To determine the optimum values of the process parameters, it is essential to find their influence on the deformation behavior of the sheet metal. The mechanics of forming are quite complicated and there are many different factors affecting the successful drawing of a blank. Forming limit plays a very important role in metal forming processes since it can be used to predict whether a blank will fracture or not. In this research, a new, simple and practically applicable equation, which consider strain hardening and thickness changes during forming process to calculation the limit drawing ratio (LDR) in cylindrical cup-drawing is derived.