Product Code: ICAL08_P106

Laser Pressure Welding of Galvanized Steel and Pure Aluminum
Authors:
Koji Nishimoto, Anan National College of Technology; Anan, Tokushima Japan
Yoshihiro Okumoto, Anan National College of Technology; Anan-shi, Tokushima Japan
Tomoki Harano, Anan National College of Technology; Anan-shi, Tokushima Japan
Hiroo Fujii, Anan National College of Technology; Anan-shi, Tokushima Japan
Ken Atagi, Anan National College of Technology; Anan-shi, Tokushima Japan
Seiji Katayama, Joining and Welding Research Institute, Osaka University; Ibaraki, Osaka Japan
Presented at ICALEO 2008

This paper proposes a laser pressure welding for joining application of dissimilar metals. In this method, a 2 kW YAG laser beam was irradiated into a wedge shaped gap of two sheets of metals between a pair of pressure rolls by a f:θ lens and scanned at various frequencies and patterns using two dimensional scanning mirrors. Then the sheets were pressed and joined by the pressure rolls. In this study, laser pressure welding of Galvanized steel (GI steel) and pure aluminum (A1050) was carried out by changing the laser power and the roll pressure. A galvanized layer and aluminum was melted so thinly as to form the solid solution layer in the welded interface. SEM observation near the joint layer revealed that the measured thicknesses of characteristic layers were about 7 μm to 20 μm. The tensile shear strength and the peel strength of the laser pressure welded joint were so high that A1050 base metal fractured at the roll pressure of more than 1.96 kN. The hardnesses of the characteristic layer were about 200 Hv to 350 Hv. From these results, such high strengths and base metal fractures were attributed to the scattered formation of the intermetallic compounds partly in the solid solution.