为了进一步了解不同厚度钢板拼焊在一起后组成的板料(差厚激光拼焊板)在各种应变路径下的成形极限,通过试验检测了0.8,1.2,1.5 mm三种厚度的ST16板料在不同组合激光拼焊下组成的板料以及其各自母材的成形极限,并研究了不同加载情况下焊缝附近的应变分布.结果表明:差厚激光拼焊板焊缝附近的成形极限低于母材的成形极限,主要取决于较薄一侧母材的成形极限;厚度差越大焊缝两侧的应变梯度越大,成形性能越差.

In order to investigate the forming limit of tailor welded blanks(TWBs) with different thicknesses low carbon steel(ST16) sheets with thicknesses of 0.8 mm,1.2 mm and 1.5 mm were welded together with the thickness combinations of 0.8 mm/1.2 mm,1.2 mm/1.5 mm,and 0.8 mm/1.5 mm.The forming limit (FL) of three base materials and three TWBs were got from experiments.The difference of the FL between base metal and TWBs was compared and the effect of the thickness combination rate was studied.Results show that the forming limit of TWBs with different thicknesses was less than that of the base material and was determined by the thin base blank.The strain gradient along the welded line increased with the thickness combination rate increase.