A hard facing alloy is applied to a surface of a substrate by making a mixture of at least two constituents whose net composition is the desired hard facing alloy composition. The constituents have different solidus temperatures, at least one of which is above a processing temperature of the substrate and another of which is below the processing temperature of the substrate. In one preferred approach, the mixture is prepared by pressing and lightly sintering the constituents in the form of powders, so that the mixture retains its shape and can be attached to the substrate surface. Then the substrate is heated to the processing temperature and maintained for a time sufficient to permit interdiffusion of the several different phases toward a homogeneous hard facing alloy composition uniformly through a major portion of the volume.