Understanding laser welding technology can better master the technology

Laser welding has become the representative of a new generation of welding in various industries, and its welding advantages have made many traditional welding disadvantages. Do you know the process of laser welding? Understand its processing process and have a deeper understanding of laser welding technology.

The first point is heat conduction welding. During the welding process, the laser beam melts the parts to be welded at the welding site, and the molten material flows in and solidifies together. The weld does not require any other polishing and finishing operations to be smooth and round. The depth range of heat conduction welding is only 1 mm or a few tenths of a millimeter. The heat conduction efficiency of the metal workpiece limits the welding depth, and the welding depth of the welding site is always less than the welding width. During the welding process, the processing temperature will rise rapidly to the vaporization temperature or above. The metal appears in the form of steam, and the welding depth will be greatly deepened, becoming a deep fusion weld.

The second point is deep penetration welding. Deep penetration welding requires a lot of power density. During the welding process, when the laser beam begins to melt the metal through energy, steam is generated. The steam increases the pressure of the molten metal and displaces part of it. If the welding continues, a deep and narrow hole filled with steam will be formed after the material is dissolved. This is the hole effect. The laser beam moves forward at the welding site, and the hole moves with it. The molten metal begins to solidify under the trace of the hole, that is, a uniform, deep and narrow internal weld is produced, and the welding depth is about ten times the welding width. The characteristics of deep penetration welding are high efficiency, fast welding speed, small heat energy affected area, and deformation within a controllable range. Deep penetration welding is used when multi-layer materials need to be welded.

The third point is active gas and protective gas. They are gases that protect the welding process during laser welding and determine the welding quality after welding. Active gas is mainly suitable for carbon dioxide laser welding to prevent the formation of plasma clouds on the surface of the workpiece and hinder the work of the laser beam. The protective gas is to ensure that the welding surface is not affected by the ambient air and to protect the non-turbulent (laminar) flow of gas to the workpiece.

The fourth point is the filling material, adding silk or powder where it is needed to be connected. Its function is to fill in too wide and irregular Fenxi, reduce welding preparation, fill in some special materials, and make the welding material better.

The fifth point is the composite welding technology. This welding method is a welding method that combines laser welding with other welding. It can be combined with inert gas shielded welding or active gas shielded welding. The composite welding technology is faster than the single-sided welder and the deformation of the parts is small.

The sixth point is laser fiber welding, where the matching parts are welded together by adding materials and brazing materials. The laser fiber welding temperature is not very high, it is only for melting the added materials, and the connected parts are only for heating. After the brazing melts, it flows into the gap of the connecting part and then combines with the surface of the workpiece. The welding strength of laser brazing is the same as the welding material, and the welding surface after welding is smooth and bright, and no further processing is required.