Experimental and analytical studies on the prediction of forming limit diagrams

Metal forming processes are widely used in industrial productions, automobile bodies, food industries, oil refineries, and liquid and gas transmission systems. Analyzing these processes is very important to reduce wastes and optimize the processes. Study of some main factors such as physical and mechanical properties of material and its formability, die geometry, die material, lubrication and pressing speed has been the topic of many research projects. In this paper, forming limit diagrams (FLDs) for LC and ULC steels and the effect of different parameters like the work-hardening exponent, n, and the plastic strain ratio, r. on these diagrams have been evaluated and simulated using ABAQUS/Standard. In this case, Hill's quadratic anisotropy function is assumed to be the yield function and the Atkins criterion is used as the failure criterion. (C) 2008 Elsevier B.V. All rights reserved.