When the laser welding machine is performing welding work, the laser power density value plays a major role. Different materials have a critical power density threshold. In order to weld, the power must exceed this critical threshold so that the material can be melted and the welding effect can be achieved. When the laser power is constant, the welding speed becomes the main factor affecting the welding strength, and the appropriate laser welding speed is the guarantee of solid welding.

In the welding industry, some people think that the faster the welding speed of the laser welding machine, the better. In fact, the laser welding speed cannot be too fast or too slow. It must be suitable. Too fast and too slow will affect the laser welding strength. Laser power and welding speed affect the depth and width of melting, and then affect the welding strength. When the laser power is constant, the welding speed becomes the main factor affecting the welding strength.

The excessive power of the laser welding machine burns the alloy elements in the weld area, which reduces the strength and mechanical properties of the weld. The high welding power also deteriorates the weld formation and increases the number of surface holes. Too high a welding speed will reduce the strength of the weld because the pores in the weld increase and the effective bearing area decreases. The welding speed and laser power together affect the welding depth. When the speed is constant, there is a critical zone for the weld strength. When the power is lower than its lower limit, the strength increases with the increase of power. This is because as the power increases, the penetration depth increases and the bonding strength also increases; when the power is greater than the upper limit of the critical zone, the strength decreases with the increase of power.