• CN:11-2187/TH
  • ISSN:0577-6686

›› 1985, Vol. 21 ›› Issue (2): 13-26.

• 论文 • 上一篇    下一篇

弹塑性有限元法分析不同型线凹模静液挤压时的应力和应变状态

谢水生;王祖唐;金其坚   

  1. 清华大学;北京有色金属研究总院
  • 发布日期:1985-03-01

THE ANALYSIS OF VARIOUS MATHEMATICALLY CONTOURED DIES IN HYDROSTATIC EXTRUSION BY ELASTO-PLASTIC FINITE ELEMENT

Xie Shueisheng;Wang Zutang;Jin Qijian   

  1. Tsinghua University General Research Institute of Non-Ferrous Metals
  • Published:1985-03-01

摘要: 静液挤压时,如凹模的型线不同,变形区的应力和流动状态是不同的。目前,静液挤压时,广泛采用圆锥模,但在挤压脆性金属时,产品经常会出现缺陷。为了研究产生缺陷的原因,应用弹塑性有限元法计算和分析了等应变型线模、余弦型线模、最短流线模、椭圆型线模及圆锥模等五种不同型线凹模在静液挤压时的应力和应变状态。结果表明,等应变型线凹模挤压时的应力和应变分布最为均匀,挤压力和塑变区内的拉应力最小,适用于挤压脆性金属。计算结果与实验比较,符合很好。计算结果对设计挤压凹模有很大的参考价值。

Abstract: The contour of die wall influences on the plastic stress and flow field of hydrostatic extrusion. At present, conic wall die is mostly used. However when it is used to extrude brittle metals, defects are often found on the products. In order to search for the cause, the stress field and flow pattern of hydrostatic extrusion with dies of equal stsain rate, cosine curve, Richmond curve, conic and elliptic curve have been computed and studied by elasto-plastic finite element method. Results show that extrusion with die of equal strain rate has the most uniform stress and strain field as well as the less extrusion pressure and tensile stress. It seems that die curve of this kind is the best contour' for extruding brittle metals. Computed results are useful for designing extrusion dies.