用有机玻璃的记忆性研究塑性变形的应变分布

PLASTIC STRAIN DISTRIBUTION ANALYSED BY MEMORY OF PMMA

有机玻璃是一种具有形状记忆性的热塑性材料。本文利用有机玻璃对圆柱体镦粗和直齿圆柱齿轮精锻的变形状态进行模拟实验 ,将变形后的试样沿子午面剖分 ,在一个剖分面上划上网格 ,然后使其恢复原状 ,利用恢复后的网格尺寸变化反向计算应变分布。本试验利用四节点平面等参元理论及塑性欧拉大变形公式 ,求各处网格的应变分量及等效应变分布。研究表明 ,利用光塑性材料记忆性确定塑性变形的应变分布是可靠的。

PMMA is one kind of hot plastic material with shape memory faculty.This paper do the cylinder upsetting and spur gear radial precision forging simulation experiments.The experiment sample is cut along meridian section after deformation and drawn grid,then the sample is resumed. The strain distribution can been calculated by the grid change. 4 nodes isoparametric element and plastic Euler large deformation equation are used to calculate the strain component and equivalent strain distribution.This research demonstrate that photo plastic material shape memory faculty is confident to define plastic deforming strain distribution.