Laser offset welding method suitable for magnesium/steel and magnesium/titanium

The invention relates to a welding method for dissimilar metals, and in particular relates to a laser offset welding method suitable for magnesium/steel and magnesium/titanium. The method comprises the following steps: (1) fixing to-be-welded magnesium and steel or magnesium and titanium on a work table, and jointing by use of zero-gap seamless joints; and (2) achieving the welding by irradiating steel or titanium with laser under the conditions of filling welding wire or not, wherein the protection gas flow rate is1 L/min to 50 L/min, the welding speed is 0.1 m/min to 1 m/min, the laser power is 1 W to 10 kW, and the laser offset 0.1 mm to 0.8 mm. The high-melting-point side material can be molten by irradiating with the laser beam, and the low-melting-point side material can be molten through heat conduction so as to achieve the connection between the two kinds of materials. When a laser beam directly irradiates a high-reflectivity material, such as a magnesium alloy, the material has low energy absorption rate. However, the laser offset welding method can solve the problem, and can reduce the defects, such as welding seams and pores, generated on the material with a low melting point or a low bolting point.