The cluster line criterion was used for optimized design of a Ni-Zr-Al alloy used as coating on the AZ91HP magnesium alloy by laser cladding. Results show that the coating mainly consists of an amorphous, two ternary intermetallic phases with Ni10Zr7 and Ni21Zr8 type structures resulting in high hardness, good wear resistance and corrosion resistance. The interface between the clad layer and the substrate has good metallurgical bond. (C) 2009 Elsevier B.V. All rights reserved.