研究镀锌钢板搭接激光焊接技术对汽车工业激光焊接具有重要意义。研究了搭接间隙对光纤激光焊接镀锌钢板焊缝成形和接头机械性能的影响，分析了预留间隙法解决镀锌钢板搭接激光焊中高压锌蒸气对焊缝的不良影响的机理，通过实验研究了激光功率和搭接间隙的工艺参数范围。研究结果表明，对于1.35 mm板厚的HC260LAD+Z 100 MB镀锌钢板搭接激光焊，间隙大于0.1 mm时，可以很好地抑制锌蒸气造成的焊接缺陷；间隙约为0.15 mm时，焊缝熔深达到最大值；4 kW激光功率对间隙的容忍度较大，对于0.05～0.2 mm板间间隙都可以得到良好的焊缝。

The research on laser lap welding of galvanized steels in automobile industry is very significant. The effects of gap on the features and mechanical properties of welding seam are analyzed. Meanwhile, the impact of setting small gap between faying surfaces on suppressing defects that caused by zinc vapor is studied and verified by experiments. The range of laser power and lap gap is also investigated. The outcome implies that for laser lap welding of HC260LAD+Z 100 MB galvanized steel sheet whose thickness is 1.35 mm, gaps exceeding 0.1 mm will suppress the defects caused by zinc vapor effectively. Penetration reaches the maximum value when the gap is about 0.15 mm. Greater laser power of 4 kW, has better tolerance on gap from 0.05~0.2 mm.