基于损伤因子的7075铝合金B柱热成形工艺优化  

Thermoforming Process Optimization for B Pillar of 7075 Aluminum Alloy Based on Damage Factor

作　　者：庄蔚敏[1] 李冰娇 解东旋[1] 

机构地区：[1]吉林大学,汽车仿真与控制国家重点实验室,长春130022

出　　处：《汽车工程》2015年第11期1353-1358,共6页Automotive Engineering

基　　金：国家自然科学基金(51075178);吉林省自然科学基金(20130101048JC)资助

摘　　要：针对仿真中难以简单判断7075铝合金热成形失效的问题,引入损伤因子作为评判失效的参数。首先,建立了7075铝合金高温损伤本构方程。随后,使用FORTRAN语言编写Ls-dyna用户自定义材料子程序,对B柱进行热成形有限元分析,研究单一参数变化对B柱成形最大损伤值的影响。最后,利用正交实验分析对成形参数进行优化,最终确定了一组最优成形工艺参数组合:板料初始温度420℃,模具初始温度60℃,摩擦因数0.15,压边力6 000N,冲压速度230mm/s。To overcome the difficulty in judging the thermoforming failure of 7075 aluminum alloy, a dam-age factor is introduced as a failure judgment parameter. Firstly, the thermal damage constitutive equation of 7075 aluminum alloy is established, with a corresponding user-defined material subroutine in Ls-dyna created with FOR-TRAN language. Then a finite element analysis is conducted on the thermoforming of B pillar to study the effects of single parameter change on the maximum forming damage of B pillar. Finally, the forming parameters are optimized by using orthogonal experiment, and a set of optimal parameters of forming process is determined： an initial sheet temperature of 420℃, an initial die temperature of 60℃, a friction coefficient of 0 . 15 , a blank-holder force of 6000N and a stamping speed of 230mm/s.

关 键 词：铝合金 B柱 损伤 热成形 工艺优化 

分 类 号：U463.83[机械工程—车辆工程]