Transition metal carbide and nitride layers have been generated by reaction of transition metals with a SiCN-precursor. Sheets of Hf, Nb and Mo were dip-coated with the polycarbosilazane ABSE and subsequently pyrolysed at 1000°C-1300°C. Carbon and nitrogen from the precursors reacted with the metals and formed carbides and nitrides in the interface area between the ceramic layer and the metal substrate. Transition metal nitride and carbide phases have excellent chemical and physical properties that make them suitable for high temperature applications. Due to the diffusion processes gradient layers of carbides and nitrides are formed which should provide for a good adhesion of the layers. The layers were found to be 2-3 μm in thickness after annealing at 1000°C and up to 20μm thickness at 1300°C. Phases of Nb_2N, HfN, HfN_(0.4)and Mo_2C were identified via X-ray diffraction. The precursor route is an excellent method to synthesise ceramic coatings on transition metal substrates at comparatively low temperature without complex equipment.
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