Evolution of microstructure in Zr55Cu30Al10Ni5 bulk amorphous alloy by high power pulsed Nd:YAG laser

In this work surface modification of Zr-based bulk amorphous alloy Zr55Cu30Al10Ni5 was carried out with pulsed Nd:YAG laser. The as-cast and modified surface of amorphous alloys at different conditions were characterized using X-ray diffraction (XRD), scanning electron microscopy (SEM) and energy dispersive spectroscopy (EDS) techniques. Phases like Cu10Zr7, CuZr2 and NiZr2 were identified which result in the enhancement of hardness of the modified alloys surface. It was observed that low laser power and prolonged irradiation time provides large nucleation frequency and limited growth rate which intern produces small spherical particle dispersion homogeneously distributed in an amorphous matrix resulting significant increase in surface hardness. (C) 2009 Elsevier B.V. All rights reserved.