Surface alloys are of great interest for improving the mechanical and/
or chemical properties of the near-surface region on metallic material
s. A new method, in situ laser surface coating of metal-matrix composi
te, 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 TiC
x particles, 0.5-0.8 mu m in size, were homogeneously distributed in t
he top half of the matrix layer.