利用光纤激光扫描焊接铝合金V型坡口,研究了坡口角度、透镜焦距、离焦量等对坡口内材料熔化行为的影响。结果表明,V型坡口对光纤激光具有明显的汇聚作用。当焦距为300mm、离焦量为0~10mm、坡口角度为5°时,坡口内可获得较好的熔化效果。进一步分析表明,这与铝对光纤激光在布儒斯特角处的吸收率不高有关,但由于每次反射会损失部分激光能量,因此光纤激光在V型坡口内的反射次数不宜过多。 The effect of groove angle, lens focal length and defocusing amount on the melting behavior of grooved material was studied by fiber laser scanning V-groove. The results show that V-groove has obvious convergence effect on fiber laser. When the focal length of 300mm, the amount of defocus 0 ~ 10mm, bevel angle of 5 °, the bevel can get better melting effect. Further analysis shows that this is related to the low absorption rate of Al-fiber laser at Brewster’s angle. However, since each reflection will lose part of the laser energy, the reflection frequency of the fiber laser in the V-groove should not be excessive.