Study on Laser Micro Welding of Nickel-plated Steel Sheet with 0.3 mm Thickness
The butt welding with 0.3 mm thick nickel-plated steel sheet was carried out using low power impulse laser and the microstructure and mechanical property of the welded joint were studied. The results show that the nickel layer on the nickel-plated steel sheet has larger effects on the laser reflection and the good weld seam cannot be gotten by direct welding. The polished away the nickel layer by sand paper before welding can improve the welding quality. The micro-laser welded joint of nickel-plated steel have fine grained region in HAZ, little martensite and fine grained ferrite and retained austenite in the welded seam. The tensile strength and hardness of the welded joint are higher than that of the base metal.