镀锌钢板的CO_2激光焊焊接性(II)

以裁焊板工业生产为背景 ,对汽车用镀锌钢板的CO2 激光切割板坯的CO2 激光焊接的焊缝性能进行了试验研究。试验中的激光焊缝屈服强度都大于母材 ,焊缝金相组织以硬度较软的针状铁素体为特征 ,包含激光焊缝的镀锌钢板仍具有优良的深冲性能 ,在焊缝附近锌层烧损小于 0 .5mm宽。镀锌层具有牺牲保护作用使得激光焊缝不易腐蚀。因此 ,裁焊板的激光焊接工艺可靠 ,从焊接角度看 ,激光切割取代裁焊板生产中剪切工艺是可行的

CO_2 laser-weldability of zinc coated steel sheets (II)

CO_2 laser butt welding of zinc coated steel sheets cut by CO_2 laser was investigated regarding with automotive manufacture. It was found that the yield stresses of the laser welding seams were larger than that of the matrix steels. The microstracture in the seems were character ized by needle-like ferrite with lower hardness. The sheets containing the laser welded seams maintained excellent deep dawning potential, and the destroyed zinc layer near the seams is less than 0.5 mm in width. The zinc layer protected the welded seams from corrosion through zinc self-sac rifice. The results indicated that the CO_2 laser butt welding is a robust technology for tailored welded blank manufacture, and laser cutting may be a promising tool in tailored welded blank manufacture.