Formation and Oxidation Resistance of NbSi2 Coatings on Niobium by Pack Cementation
NbSi2 coatings were formed on niobium by halide-activated pack cementation process. The as-coated niobium samples were oxidized in air up to 1723 K by thermogravimetry method. The surface and cross-sectional morphology, phase composition and element distribution of the NbSi2 coatings before and after oxidation were characterized by SEM, XRD and EPMA. The results show that the as-formed coatings consist of single phase of hexagonal NbSi2 and the oxidation resistance of pure niobium can be greatly improved by pack siliconizing.
Wei Pan, Jianghong Gong, Chang-Chun Ge and Jing-Feng Li
M. Li et al., "Formation and Oxidation Resistance of NbSi2 Coatings on Niobium by Pack Cementation", Key Engineering Materials, Vols. 280-283, pp. 907-910, 2005