激光液态填充焊与常规激光填丝焊特性的对比研究

Comparative Study on Laser Welding with Pre-Melting Liquid Filler and Conventional Filler Wire

针对激光填丝焊过程中的焊丝对入射激光能量的反射、匙孔不稳定、光丝对中精度要求高等问题,以铝合金为材料,对比研究了激光液态填充焊与激光填丝焊的填材熔化与填充特性。结果表明,激光液态填充焊中焊丝依靠电弧的作用熔化,液态金属依托底部固态焊丝的导向流入到熔池中,填充过程连续稳定,降低了焊丝对入射激光能量的反射。相比激光填丝焊,熔化的焊丝端部距离匙孔边缘较远,避免了填材对匙孔的直接冲击,而且熔池尺寸较大有利于气泡逸出,降低了铝合金气孔率,明显提高了高速焊、送丝精度的适应性。

The laser welding with pre-melting liquid filler is developed to solve the problems, such as the reflection of incident laser energy by filler wire, and unstable keyhole in the process of laser welding with filler wire. The melting and filling characteristics of aluminum alloy filler material about laser welding with premelting liquid filler and filler wire are comparatively investigated. The results show that, in laser welding with pre-melting liquid filler, the filler wire is melt by arc, the filling stage is continuous and stable due to liquid metal wire relying on the guide role of the solid-state wire on the bottom inflow to the weld pool. It reduces the reflection of incident laser welding energy. Compared with laser welding with filler wire, the liquid filling material is far from keyhole edge so that it avoids the direct impact of fill material to the keyhole and the molten pool has a big size for the escape of bubbles. So it will help reducing the aluminum porosity. Stability of keyhole is improved in high speed welding. And it significantly improves the adaptability about the high-speed welding and wire feeding accuracy.