焊缝对拼焊板纵向拉伸成形性能的影响规律

Effect of Weld on Formability of Longitudinal Tailor Welded Blanks

摘要:

基于焊缝和母材应变相等的假设，推导出拼焊板纵向拉伸时平均延伸率与母材材料参数、焊缝材料参数及母材与焊缝初始宽度比之间的关系.在母材材料参数一定时，采用有限元方法分析了焊缝材料参数、初始宽度比对拼焊板纵向拉伸抗拉强度和平均延伸率的影响规律.结果表明,焊缝强度系数K对拼焊板纵向拉伸抗拉强度的影响较为显著，而对平均延伸率影响较小；焊缝硬化指数n对抗拉强度影响很小，对平均延伸率影响较大；初始宽度比对试件拉伸性能的影响存在一个敏感区域(0~20)，当初始宽度比大于20时，拼焊板随其变化趋于平缓.

Abstract:

Based on the “isostrain hypothesis”,the relationship was obtained between mean elongation and influence factors such as base material properties,weld properties and initial width ratio of the base metal and weld.The finite element method was employed to analyze the influence laws of the weld properties and initial width ratio on the tensile strength and mean elongation with constant base material properties.The results demonstrate that the strength coefficient K of the weld has more influence on the tensile strength and less effect on the mean elongation;the hardening coefficient n is just contrary;initial width ratio has significant effect on them in its sensitive area (0~20) and when initial width ratio exceeds 20,the effect becomes subtle.