应用改进的大变形应变分析方法分析精冲挤压复合工艺

Analyzing Combined Fine Blanking and Extrusion Process Using Improved Strain Analysis Technique in Large Deformations

针对英国Hs櫣提出的基于实验的大变形应变分析方法的不足 ,借鉴有限元方法中的一些技巧 ,对其进行了相应的改进 ,并据此编制了等效应变计算程序。用原方法和改进方法分别对精冲挤压复合工艺进行了等效应变分布计算 ,结果表明改进方法优于原方法。进一步对变形试件的子午面进行了显微硬度测量 ,并将所测硬度分布的规律与改进法所获得的等效应变分布规律进行了对比 ,可见二者之间的一致性 。

The large strain analysis technique based on the experiments was developed by T. C. Hsu in U. K. Considering the shortcomings in the technique, some methods used in the FEM were introduced to improve the large strain analysis technique and a corresponding program was developed to calculate the equivalent strain distribution. Both the original technique and the improved one were applied to the combined fine blanking and extrusion process to obtain the equivalent strain distributions. The results show that the improved technique is better than the original one. Furthermore, the micro hardness distributions on the meridian plane of the specimens were measured to compare and verify the simulated strain results. It is found that the law of the micro hardness distributions is in accordance with that of the equivalent strain distributions from the improved technique. All the results show that the improved technique is effective to analyze the strain distribution in the metal forming processes.