The project is on laser-induced methods for processing transition metal carbides and nitrides. These methods, based upon laser melting and decomposition, will be used to produce layers of carbides and nitrides of W and Ti. By controlling the laser parameters and substrate variables, microstructures ranging from amorphous to polycrystalline can be obtained. The laser-induced chemical vapor deposition will be used to form layers and powders of carbides and nitrides of W and Ti. The chemical composition and stoichiometry of carbides and nitrides can be controlled by adjusting partial pressures of constituent gaseous species in the reaction chamber. These materials will be characterized using TEM/STEM, Auger, SIMS, and RBS techniques in terms of mircostructures, chemical composition, stoichiometry, and homogeniety. Amorphous films of carbides and nitrides produced by laser-induced photolytic decomposition are expected to have unique physical and mechanical properties. Selected films will be evaluated by microhardness and electrical resistivity measurements. The variation of resistivity with temperature will be studied as a function of stoichiometry and microstructure for various films.
