Surface alloys are of great interest for improving the mechanical and/or chemical properties of the near-surface region on metallic materials. A new method, in situ laser surface coating of metal-matrix composite, is described, by which to produce a surface composite layer. Using this process, gamma-Ni-TiCx composite surface layers were achieved on mild steel; they exhibited increased hardness, and in situ formed TiCx particles, 0.5-0.8 mu m in size, were homogeneously distributed in the top half of the matrix layer.