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A method is provided for depositing and thermally diffusing a boride or a carbide of a refractory metal on a substrate of a workpiece. A layer of the refractory metal is deposited on the substrate. At least one of the elements boron and carbon is deposited from a source other than the workpiece on t

A method is provided for depositing and thermally diffusing a boride or a carbide of a refractory metal on a substrate of a workpiece. A layer of the refractory metal is deposited on the substrate. At least one of the elements boron and carbon is deposited from a source other than the workpiece on the workpiece having the refractory metal layer. The workpiece is heated at a temperature and for a time period sufficient to diffuse at least a portion of the deposited refractory metal into the substrate and at least a portion of the deposited boron or carbon into the refractory metal layer and the substrate to form a substantially uniform and metallurgically bonded layer of the boride or carbide of the refractory metal on the substrate.

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1. A method of providing a boride or carbide of a refractory metal on a substrate of a workpiece comprising the steps of:(a) providing a first molten salt bath of an anhydrous fused salt electrolyte in an inert container, the molten salt lath comprising a substantially eutectic mixture of at least o

1. A method of providing a boride or carbide of a refractory metal on a substrate of a workpiece comprising the steps of:(a) providing a first molten salt bath of an anhydrous fused salt electrolyte in an inert container, the molten salt lath comprising a substantially eutectic mixture of at least one halide from the group consisting of alkali metal halides and alkaline earth metal halides and a reducing agent for a refractory metal; (b) immersing an anode comprising the refractory metal in the first molten salt bath; (c) immersing a cathode comprising the workpiece in the first molten salt bath, the workpiece being electrically conductive; (d) electrodepositing a layer of the refractory metal on the workpiece; (e) heating the workpiece with the electrodeposited refractory metal thereon to a first temperature in a range of about 700.degree. C. to about 900.degree. C. for a first time period sufficient to diffuse at least a portion of the electrodeposited refractory metal into the substrate such that a refractory metal layer is metallurgically bonded to the substrate; (f) providing a second molter salt bath in an inert crucible, the second molten salt bath comprising an anhydrous fused salt electrolyte comprising at least one halide from the group consisting of alkali metal halides and alkaline earth metal halides and a compound containing at least one second element from the group consisting of B and C; (g) immersing the cathode comprising the workpiece having at least a portion of the electrodeposited refractory metal diffused therein in the second molten salt bath; (h) electrodepositing a layer of the second element from the second molten bath on said workpiece having the refractory metal layer; and (i) heating the workpiece having the second element electrodeposited on the layer of the refractory metal to a second temperature in the range of about 700.degree. C. to about 900.degree. C. for a second time period sufficient to diffuse at least a portion of the boron or carbon into the refractory metal layer and the substrate to form a boride or carbide of the refractory metal and to provide a substantially uniform and metallurgically bonded layer of the boride or carbide of the refractory metal on the substrate.