Product Code: ICAL07_1001

Technology Development on Dual Beam Laser Lap Welding of Mg Casting Alloys for Automotive Applications
Authors:
Feng Lu, Chrysler LLC; Auburn Hills MI USA
Mariana Forrest, Chrysler LLC; Auburn Hills MI USA
Steve Logan, Chrysler LLC; Auburn Hills MI USA
Presented at ICALEO 2007

Magnesium casting alloys are very appealing materials for automotive applications due to their excellent specific strength (weight reduction), sound damping capability, castability, electromagnetic interference shielding ability and etc. Laser welding is also the desired method of joining these materials, which provides high productivity and structural integrity. However, there is a major challenge for laser welding Mg alloys: the propensity of porosity formation within the weld. In this paper, the porosity formation mechanism and the factors that influence the porosity formation in a lap joint will be discussed first. Following this, a new technology based on dual beam welding will be elaborated along with recent preliminary results. The results show that this newly developed technology can significantly reduce porosity and achieve high welding speed.