Abstract

The oxidation behaviors of Ti powder thermal spray coated Mo-Si-B alloys have been investigated in order to identify the underlying mechanism for the effect of precursor Ti coatings on Mo-Si-B alloys. Pure Ti powder was thermally sprayed on the two phase alloy (Mo (solid solution)+T2(Mo₅SiB₂)) fabricated by arc melting elemental components. The oxidation tests performed at 1100 °C show that the Ti powder was tightly bonded and reacted with the surface of the substrate, and TiO₂ layer was formed at the outer surface of the coated Ti layer as a result of oxidation exposure. The oxidation behaviors of pure elemental component coated Mo-Si-B alloys have been discussed in terms of microstructural observations during oxidation tests.

Keywords: Alloys, coating, Mo alloys, oxidation, scanning electron microscopy.