铝/钛异种合金激光深熔钎焊试验分析

Analysis of laser deep penetration brazing of aluminium and titanium alloys

采用3500W板条式扩散冷却CO2激光器,利用激光深熔钎焊原理对3mm厚6061铝合金和钛合金进行异种金属激光焊接.聚焦激光作用在铝合金一侧为深熔焊,熔化的铝合金浸润钛合金界面形成钎焊接头.拉伸试验发现,断裂均发生在界面处,通过Olympus金相显微镜观察发现断口存在部分未熔合.结果表明,降低焊接速度,并采用合适的偏焦量,负离焦量和偏转角度可以改善界面的熔合.

Based on laser deep penetration brazing process, a CW ROFIN-SINA laser with a output power of 3.5 kW was used to join aluminium and titanium alloys with a thickness of 3 mm. The aluminium melted by the focused laser beam deep penetration was wet the interface of titanium to form a brazing joint. The tensile test results show that the fracture happens on the interface, and incomplete fusion parts on the interface are observed with an Olympus metallographic microscope. Through studying the influence of process parameters on the incomplete fusion rate, the fusion of the interface will be improved by reducing the welding speed and optimizing the beam spot offset, defocusing distance and deflexion angle of laser.