Transactions of Nonferrous Metals Society of China
JOURNAL OF RAILWAY SCIENCE AND ENGINEERING
|Vol. 17 No. 6 December 2007|
（1. Kanthal AB, Box 502, SE-734 27 Hallstahammar, Sweden; 2. Department of Materials and Manufacturing Technology, Chalmers University Technology, SE-412 96 Gothenburg, Sweden ）
Abstract: Cr-alloyed MoSi2 was compared with monolithic MoSi2 with respect to oxidation at 450 ℃ for 456 h. Phases formed on Cr-alloyed MoSi2 after exposure are Cr2(MoO4)3, MoO3, and cristobalite (SiO2) according to X-ray diffraction results. Monolithic MoSi2 forms MoO3 and mainly amorphous SiO2. X-ray photoelectron spectroscopy indicates that the main oxidation product on the outermost surface is SiO2 for all studied samples. The samples form a relatively loose oxide but the oxide adherence improves with increasing Cr content. It is indicated that Cr addition can benefit pesting control in MoSi2.
Key words: molybdenum silicides; pesting; oxidation; alloying