汽车工程
汽車工程
기차공정
Automotive Engineering
2015年
11期
1353-1358
,共6页
铝合金%B柱%损伤%热成形%工艺优化
鋁閤金%B柱%損傷%熱成形%工藝優化
려합금%B주%손상%열성형%공예우화
aluminum alloy%B pillar%damage%thermoforming%process optimization
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6000N,冲压速度230mm/s。
針對倣真中難以簡單判斷7075鋁閤金熱成形失效的問題,引入損傷因子作為評判失效的參數。首先,建立瞭7075鋁閤金高溫損傷本構方程。隨後,使用FORTRAN語言編寫Ls-dyna用戶自定義材料子程序,對B柱進行熱成形有限元分析,研究單一參數變化對B柱成形最大損傷值的影響。最後,利用正交實驗分析對成形參數進行優化,最終確定瞭一組最優成形工藝參數組閤：闆料初始溫度420℃,模具初始溫度60℃,摩抆因數0.15,壓邊力6000N,遲壓速度230mm/s。
침대방진중난이간단판단7075려합금열성형실효적문제,인입손상인자작위평판실효적삼수。수선,건립료7075려합금고온손상본구방정。수후,사용FORTRAN어언편사Ls-dyna용호자정의재료자정서,대B주진행열성형유한원분석,연구단일삼수변화대B주성형최대손상치적영향。최후,이용정교실험분석대성형삼수진행우화,최종학정료일조최우성형공예삼수조합：판료초시온도420℃,모구초시온도60℃,마찰인수0.15,압변력6000N,충압속도230mm/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.
