(1) spot diameter
The diameter of the spot has a greater influence on the spreading of the solder. The spot diameter is too small, the laser is concentrated on the solder, the heating of the base material is insufficient, and the solder cools too fast when spreading on the base material, so that the solder is not easy to spread; the spot diameter is too large, and if the laser power is insufficient, it cannot be melted in time. If the laser power is sufficient, the welding wire will seriously burn the base metal. For the roll butt joint, the spread of the solder is sufficient when the spot diameter is substantially the same as the weld width (filler width).
(2) Laser power
The speed at which the wire melts depends on the amount of laser energy, ie the laser power. When the laser power is insufficient, the welding wire has a slow melting speed, insufficient spreading, long working time and low production efficiency; when the laser power is too large, the welding wire melts fast, and if the wire feeding speed cannot keep up, the weld seam exhibition Intermittent. The maximum laser power is limited by the equipment. The adjustment of the laser power is mainly based on its matching with the welding speed and the wire feeding speed.
(3) Welding speed and wire feeding speed
The welding speed determines the length of the working time and the level of production efficiency. Therefore, the appropriate welding speed should be selected according to the laser power that the equipment can provide to improve the production efficiency. Generally, the faster the welding speed, the higher the production efficiency, but for a circular arc weld or a transition weld with a small radius, the centrifugal force generated by the excessively fast welding speed will hinder the spreading of the molten solder and make the welding process unstable. .
After selecting the welding speed (the maximum value is determined by the performance of the robot), the appropriate wire feed speed is matched according to the amount of weld fill. If the wire feeding speed is too fast, the solder material will accumulate on the surface of the weld, which will affect the appearance quality. If the wire feeding speed is too slow, the surface of the weld will be sunken. Too little filling will affect the welding strength of the weld. Of course, the adjustment of the wire feed speed also needs to consider the size of the laser power.
(4) Other factors
In addition, the wire feeding angle, the inclination angle of the welding head and the hot wire current during the hot wire also have a great influence on the welding quality. In the process of process debugging, the above factors must be comprehensively considered to obtain the best welding quality.