实心圆试件扭转试验确定大应变本构关系

DETERMINE FINITE-STRAIN STRESS-STRAIN RELATIONSHIP BY TORSON TEST WITH CYLINDRICAL SPECIMENS

提出并完成了通过实心圆轴扭转试验建立大应变本构关系的方法．它比单向拉伸试验所 得到的本构关系更为精确．因拉伸实验变形较大时试件伸长和变细对测量结果有影响；尤其在 “颈缩”后，很难对有关力学量作有效测量和分析．即扭转本构关系的描绘更为完整．以低碳钢 为例，扭转本构关系所描述的有效区间比拉伸本构关系大十余倍．该方法将有利于探讨研究更 大应变下的材料力学行为．

This paper deals with a study of Finite-strain stress-strain relationship by torson test with cylindrical specimens. How to establish large strain constitutive relationship by a torsion test with solid circular shafts is proposed in the article. Because the specimen become necking under axial tension, it's impossible to make the effective measurement and analysis for the mechanical property of the specimen. But this method of the article does not affect the result for axial tension and thinning of the specimen. Therefore, this kind of large strain constitutive relationship is much more accurate than that obtained from a axial tension test. Such as low carbon steel, the effective strain interval described by the torsion constitutive relationship is ten times wider than that in the axial tension constitutive relationship. Present description of the torsion constitutive relationship is more complete. While the method in the paper could solve the problem and greatly widens the interval described. In addition, it could benefit for the exploring and researching on the mechanical property of the large strain material.