Short pulse irradiation of magnesium based alloys to improve surface properties

Various magnesium alloys were irradiated with an XeCl excimer laser. The su rface of the irradiated areas showed a typical wavy structure caused by the expanding plasma. The resulting roughness was significantly affected by th e alloying elements used. Investigations of the microstructure by SEM and T EM revealed supersaturated structures. In the case of AZ 91 an amorphous la yer was produced probably as a result of trapping of oxygen. The refinement and homogenisation of the microstructure led to improved corrosion resista nce. (C) 1999 IoM Communications Ltd.