Rigid-plastic finite-element method for analysis of three-dimensional rolling that requires small memory capacity

Abstract

At present, caliber rolling is analyzed using the three-dimensional rigid-plastic finite-element method. In this paper, a new method of analysis which requires less memory capacity than the conventional method is proposed. In the conventional method, the shape of the whole region is updated after the functional of the region is minimized, whereas in the proposed method, the shape of part of the region (large region) is updated after the functional of the large region is minimized. The load, torque, material shape, hydrostatic stress and equivalent strain rate obtained using the proposed method agree with those obtained using the conventional method within the allowable range of convergent error. Also, although the computation time for the proposed method is rather long compared with that for the conventional method, the memory capacity required for the proposed method is small compared with that for the conventional method. Finally, analysis of various types of caliber rolling in which the number of finite elements in the large region coincides with that in the whole region in analysis using the conventional method is carried out and reasonable stress and strain distributions are obtained.