A kind of laser welding method of galvanized steel sheet

Abstract

The invention relates to a laser splicing welding method for a galvanized steel sheet. The laser splicing welding method is characterized by comprising the following steps: step 1, base metal is provided and located; step 2, a laser welding system is provided; step 3, the laser welding system is started up, a protective gas sprayer nozzle blows a protective gas, and a laser beam transmitted by a laser welding head is perpendicularly irradiated onto the upper surface of a workpiece; step 5, a temperature sensor acquires the temperature of the back side of the base metal in real time, and the laser welding head and a high-pressure gas column nozzle are rotated when the acquired temperature reaches or exceeds the gasification temperature value of the base metal to ensure that the laser welding head is inclined relative to the upper surface of the workpiece and the high-pressure gas column nozzle is perpendicularly aligned with the upper surface of the workpiece; step 6, a gas supply valve of the high-pressure gas column nozzle is controlled to ensure that inert gas columns jetted by the high-pressure gas column nozzle penetrate welding pores and the laser welding head continues to perform welding; and step 7, the welding process is finished. The high-pressure tiny gas column assist in maintaining the pores, so that the stability of the welding pores and a weld pool is improved.

Description

technical field [0001] FIELD OF THE INVENTION The present invention relates to a laser welding method, in particular to a laser lap welding method for galvanized steel sheets. Background technique [0002] At present, there are three main welding processes for galvanized steel: resistance spot welding, arc welding and laser welding. For resistance spot welding, due to the existence of galvanized layer, the electrode is easy to alloy the zinc layer during welding, which reduces the life of the electrode. When arc welding galvanized steel is used, due to the low boiling point of zinc, when the arc first touches the galvanized layer, the zinc gasifies rapidly, and the generated zinc vapor is sprayed outward, which easily causes slag particles, pores, and spatters to occur during welding. , Incomplete fusion and cracks and other welding defects, the stability of the arc is also affected, the welding quality is reduced, and a large amount of smoke and dust will be generated duri...

AI Technical Summary

Problems solved by technology

[0007] The purpose of the present invention is to solve the problem that the welding process is extremely unstable and prone to defects such as splashes, pores, and lack of fusion in the current laser welding process of galvanized steel sheet joints

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