Upper bound analysis of thixotropic extrusion processes of semi-solid magnesium alloys

来源期刊：中国有色金属学报(英文版)2005年第z3期

论文作者：闫洪 杨滨 夏巨谌

文章页码：227 - 231

Key words：semi-solid magnesium alloys； thixotropic extrusion； upper bound method

Abstract: The methodology was used to conduct the upper bound analysis of thixotropic extrusion process of semi-solid metal. The calculated formulas of deformed power were derived. The relationship among relative stress, frictional factor and die semi-angle were obtained. The relative stress increases with increasing frictional factor, whose value increases with increasing area reduction ratio of a certain die semi-angle. The relative stress firstly decreases and then increases with increasing die semi-angle at a certain area reduction ratio. So, the optimal die semi-angle exists with the corresponding minimum relative stress. The calculated results are in agreement with the experimental ones, which are applied to directing technological practice of axis-symmetry forward extrusion of semi-solid magnesium alloys.