Application of Laser Welding in Automobile Industry
A large number of laser welder robots are used in the production lines of the three major American automobile groups (GM, Ford, Chrysler) and European automobile manufacturing companies (such as RENAULT, VOLVO, AUDI, BENZ and BMW). The roofs of other brand models are all laser welded. Mercedes-Benz, BMW, Volkswagen, Volvo and many other world-renowned automobile companies have applied laser welding technology to the body manufacturing process to ensure product quality and technological advancement, which means that modern automobile manufacturing is inseparable from laser welding.
1. Introduction to Laser Welding
In automobile body manufacturing, the more mature applications of laser welding are roof laser welding and rear cover laser brazing technology, as well as blank welding. The laser welding process has the advantages of reducing the weight of the body and increasing the rigidity of the body.
2. Laser welding automotive application case
In the 1980s, foreign automobile brands gradually adopted laser welding in automobile body manufacturing. The application of laser welding in the automobile industry is mainly manifested in the following aspects:
2.1 Roof laser brazing
In the robot programming and welding practice of the roof, the key is to determine the size and relative position of the focus. As shown in Figure 4, the cone represents the incident laser light, the spot represents the laser focus falling on the surface of the weld, and the two overlapping shadow blocks represent the roof and side panel parts to be welded, respectively. The size of the focus can be changed by adjusting the distance L between the focusing lens group and the upper and lower welding seam, and the position of the focus relative to the roof and side frame can be determined by adjusting the distance to the left and right.
2.2 Laser Tailored Blank Welding
Tailored welded blanks are not only an extension product of the steel industry, but also one of the important raw materials of the automobile industry, occupying an important position in the steel and automobile manufacturing industries. Tailored laser welding is to “cut” steel sheets of different thicknesses, strengths, and materials into blanks of suitable size and shape, and then laser-weld them into sheets that can be punched. The use of laser tailor welding can save material consumption, reduce the weight of components, save the process and assembly workload, reduce costs, improve the dimensional accuracy of the body, reduce the tolerance of parts, and improve the structural rigidity and safety of the vehicle. At the same time, the steel can be fully utilized.
2.3 Laser welding application of other components
In order to improve the comfort and smoothness of the vehicle, most modern cars (especially sedans) are equipped with shock absorbers inside the suspension system, and hydraulic shock absorbers are the main ones. The two-way cylindrical shock absorber is widely used due to its small mass, stable performance and reliable operation. Since the shock absorber oil storage cylinder is subjected to high pressure during the working process, it must have good air tightness and tensile fracture resistance.