Abstract:

The parabolic velocity field was first introduced into an upper bound analysis of the hot extrusion process of rod. The plentiful and reliable information was obtained through optimization of the upper bound model for hot extrasion process with respect to the pseudo independent parameter. The comparison between the calculated results and the experimental data available in the relevant literature indicates that the model is accurate enough for determination of extrusion force. By making use of the proposed model, a systematic study of dead zone, optimal die angle and extrusion force have been performed. The findings presented in the paper may be used to guide the metal forming processes.

Key words: shells of revolution, transfer matrix method (TMM), truncated conical shells