Magnesium alloys laser (Nd:YAG) cladding and alloying with side injection of aluminium powder

The development of the high purity magnesium alloys (such as WE43) incites the designers to reconsider them, and the car industry appears, these days, the most interested to use this kind of alloy. However, due to their ignitability and tendency to oxidation, magnesium alloys require surface treatments. A series of experiments was carried out in order to improve the corrosion resistance of two types of magnesium alloys, WE43 and ZE41. In most cases, the substrate surface was treated before laser interaction. Side injection of aluminium powder under a 3 kW cw Nd:YAG laser was employed. The deposited layers present very good bond properties. The resulting microstructure was analysed and some mechanical properties determined, such as hardness, which is increased due to the Al3Mg2 and Al12Mg17 intermetallic formation. The results obtained represent an important step to achieve an enhanced corrosion resistance for magnesium alloys. # 2003 Elsevier B.V. All rights reserved