摘要
在分析现有镦粗、拔长变形工序中难变形区对大型锻件锻造过程变形分布和应力状态影响的基础上,提出一种新的拔长工艺——凹面砧拔长。借助数值模拟方法和物理模拟方法比较了普通平砧与凹面平砧、普通V砧与凹面V砧拔长过程中大型锻件内部的等效应变、静水应力和空洞缺陷的闭合情况。结果表明,对应力状态而言,在变形量相同的情况下,对于凹面平砧锻造(CFAF)工艺,静水应力提高近30%,对于凹面V砧锻造(CVAF)工艺,静水应力提高近50%。对变形而言,静水应力相同情况下,CFAF工艺减少压下量33.5%;CVAF减少压下量26.5%。对空洞缺陷而言,凹面砧拔长空洞变形后的椭圆度较普通拔长小10%以上。与其他特殊拔长方法比较,凹面砧拔长有操作方便,附具简单的优点。
Based on the analysis of the influence of hard-to-deform region on the distribution of stress and strain on forgings in current upsetting and drawing, a new drawing technology named concave anvil drawing is put forwards. By means of numerical simulation and physical simulation, different effects of conventional flat anvil and concave anvil, conventional V-shape anvil and concave V-shape anvil on the equivalent deformation, status of hydrostatic pressure and voids crushing in forgings during drawing are compared. It shows that as far as statuses of stress are concerned, on the condition that the deformations are same, concave flat anvil forging（CFAF） increases hydrostatic pressure by 30% , concave V-shape anvil forging（CVAF）, 50%; as far as deformations are concerned, on the condition that the hydrostatic pressures are same, CFAF decreases reduction by 33.5%, CVAF, 26.5%; as far as void is concerned, by employing concave anvil the ovality of the void is 10% smaller than that by employing conventional anvil. Compared with other special methods, concave anvil drawing methods are more convenient to use and don＇t need complicated auxiliary tools.
出处
《机械工程学报》
EI
CAS
CSCD
北大核心
2007年第11期224-228,共5页
Journal of Mechanical Engineering
关键词
大型锻件
锻造
拔长
Large forgings Forge Drawing
作者简介
任运来，男，1958年出生，工学博士，教授。主要从事塑性成形理论及工艺的教学与科研工作。获省部级科学技术进步二等奖2项、三等奖1项，发表论文近50篇。E—mail：yandaauto@ysu．edu.cn
