铝合金5A06激光拼焊板的接头性能及组织研究

利用拉伸试验机、金相显微镜、扫描电镜分别研究了铝合金5A06不等厚激光拼焊板的接头力学性能及组织特点。结果表明,拼焊板的纵向拉伸性能较差,延伸率δ降低幅度较大,拼焊板横向拉伸性能与试样上薄板所占比例关系很大,当薄板占较大比例时,拼焊板具有较大的延伸率,拼焊板的拉伸变形能力随着薄板所占比例的减小而逐渐变差；拼焊板的焊缝组织极为细小,在熔合线附近开始向焊缝中心生长的是树枝状晶,在焊缝中心是等轴晶。

Study on the mechanical and microstructure characteristics of 5A06 Aluminum Alloy Laser TWBs with different thickness

Using tensile tests,mierosCO_2py and SEM.,the mechanical and mierostrueture characteristics of the welded joints were evaluated,and the effect of the weld distribution on the plastic formability of the TWB (tailor welded blanks) were analyzed.The results indicate that in a wide range of parameters for this alloy sheet with different thickness,the weld appearance is very well.The to- tal elongation in the longitudinal direction for the laser welds decreased greatly.The specimens of the TWB in the transverse direction were all fraetured on the base metal,and the duetibility of the TWB is effected by percent of the thinner sheet in a TWB.The total e- longation increased with percent of the thinner sheet.The microstructure of the welds was cellular dendrie structure.It was the finer equi-axed grains in the center of weld.