摘要
依据圆腔凹模中液压胀形件顶点材料的变形,是在其板面内的两个主应力同等作用下进行的。本文应用最近发展的塑性异性理论,建立了这两个主应力的差值的预测式。对几种金属板料的计算和实验验证表明,预测结果良好,精度是令人满意的。
According to the characteristics that the two principal stresses in plane at thepole of a bulging speciman in a die with circular cavity are playing equally important role inleading the deforming of material here,a method predicting the quantitative difference betweenthese two principal stresses is developed in the present paper.A non-quadratic orthotropic yieldcriterion is used and the dependence of r-value on strain is considered in this method.A comparison between the predicted ε_(90)-ε_0 and average value of dε_(90)/dε_0 using thismethod and the experimental data for several kinds of orthotropic sheet metal shows that theyare in good agreement.These indirectly prove that the present method predicting the differencebetween the two principal stresses at the pole of a bulging speciman is accurate.
基金
国家自然科学基金
5870065
关键词
材料
应变
正交异性板
液压膨胀
orthotropic sheet
bulging
pole of a specimen
difference between principal stresses
