Laser welding is an efficient and precise welding method which uses high energy density laser beam as heat source. Laser welding is one of the important applications of laser material processing technology. As one of the two basic modes of laser welding (the other is heat conduction welding), laser deep penetration welding is widely used.

Laser welding is an efficient and precise welding method which uses high energy density laser beam as heat source. Laser welding is one of the important applications of laser material processing technology. As one of the two basic modes of laser welding (the other is heat conduction welding), laser deep penetration welding is widely used.

The factors affecting the laser fusion welding effect are as follows:

1. The material itself

The laser absorption of the welder is closely related to the efficiency of laser welding. There are two factors affecting the absorption rate of the laser material:

(1) Material resistance system, through the measurement of the absorption rate of different materials polishing surface, it is found that the absorption rate of the material to the laser is proportional to the square root of the resistance coefficient, and the resistance coefficient changes with the change of temperature;

(2) The surface state of the material has an important effect on the absorption rate of the beam, so it has an obvious effect on the welding effect;

2. Laser power density

Before deep fusion welding, the laser spot must be focused to make it have a high enough power density, so the laser power density has a decisive influence on the weld formation. The laser power also controls the penetration depth and welding speed. For a certain diameter of laser beam, when the laser power increases, the depth of penetration will be deepened, and the welding speed will be faster.

3. Welding speed

In the process of deep penetration welding, the welding speed is inversely proportional to the penetration depth. If the welding speed is increased while keeping the laser power constant, the heat input will decrease and the penetration will also decrease. Therefore, properly reducing the welding speed can increase the melting depth, but too low speed may lead to the material transition melting, workpiece welding phenomenon.

4. Focus position

In deep penetration welding, the focus position is very important to maintain sufficient power density. The change of the relative position between the focus and the workpiece surface directly affects the width and depth of the weld. Only when the focus is located in the appropriate position within the workpiece surface, the obtained weld can form a parallel section and obtain the maximum penetration depth.

Nowadays, the development of laser industry is more and more extensive, and more and more people know laser welding. Laser welding has the incomparable advantages of traditional welding, of course, in use, or need to choose the welding method according to their own situation.