Mo sub(5)Si sub(3)-B and MoSi sub(2) deposits fabricated by radio frequency induction plasma spraying

Induction plasma-spray processing was used to produce free-standing parts of Mo sub(5)Si sub(3)-B composite and MoSi sub(2) materials. The oxidation resistance, up to 1210 degree C, of the Mo sub(5)Si sub(3)-B composite was compared with MoSi sub(2), which is known to be resistant to high-temperature oxidation. The deposits were oxidized isothermally in air at atmospheric pressure. The structural performance of these materials under high-temperature oxidation conditions was found to depend on the boron content in the specimens. In particular, the composite containing 2 wt.% boron exhibited excellent resistance to oxidation, as indicated by the specimen mass change, which was found to be near zero after the 24 h oxidation test.