开式冷挤压成形极限变形程度的理论及实验研究

本文应用流函数方法 ,给出了实心轴及厚壁管件无芯棒开式冷挤压成形的动可容连续速度场 ,运用上限法建立了变形功率与各主要参数间的函数关系。提出了极限变形程度的判别准则 ,借助优化方法得到各参数组合下的理论极限变形程度 ,并进行了实验验证。通过理论计算和大量的实验数据 ,讨论了各主要参数对开式冷挤压成形极限变形程度的影响规律 ,提供了低碳钢开式冷挤压成形极限变形程度数据。

THEORETICAL AND EXPERIMENTAL STUDY ON MAXIMUM REDUCTION OF OPEN DIE COLD EXTRUSION

In the paper,the kinetically admissible continuity velocity field of open\|die cold extrusion for axis and open\|die cold extrusion without mandrel for thick\|walled tube are given with stream function method and the mathematical relations between deformation power and the principal parameters is established by means of upper\|bound method.The theoretical maximum reductions under the condition of all combinations of the parameters are obtained,which is verified by the experiments,based on the maximum reduction criterion and the optimism method (optimization).On the basis of a large amount of the theoretical calculation experimental data,the influences of the parameters,as a result,the maximum reductions of open\|die cold extrusion for the low carbon steel parts are provided.