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The present invention is directed to methods for formation of refractory carbide, nitride, and boride coatings without use of a binding agent. The present invention is directed to methods of creating refractory coatings with controlled porosity. Refractory coatings can be formed from refractory metal, metal oxide, or metal/metal oxide composite refractory coating precursor of the 9 refractory metals encompassed by groups 4-6 and periods 4-6 of the periodic table; non-metallic elements (eg Si & B) and their oxides (ie SiO 2 & B 2 O 3) are also pertinent. The conversion of the refractory coating precursor to refractory carbide, nitride or boride is achieved via carburization, nitridization, or boridization in the presence of carbon-containing (eg CH 4), nitrogen containing (eg NH 3), and boron-containing (eg B 2 H 6) gaseous species. Any known technique of applying the refractory coating precursor can be used. The porosity of …