High-temperature oxidation process of intermetallic compound Ti-42 at % Al

• Published in: Journal of materials science Vol. 28; no. 4; pp. 1067 - 1073
• Main Authors: TAKASAKI, A, OJIMA, K, TANEDA, Y, HOSHIYA, T, MITSUHASHI, A
• Format: Journal Article
• Language: English
• Published: Heidelberg Springer 01-01-1993
• Subjects: Applied sciences; Corrosion; Corrosion mechanisms; Exact sciences and technology; Metals. Metallurgy; Titanium alloy; Corrosion mechanism; Corrosion; Oxide layer; Intermetallic compound; Temperature effect; Oxidation; Air; Kinetics; Experimental study; Corrosion product; Titanium Aluminium Alloys
• ISSN: 0022-2461; 1573-4803
• DOI: 10.1007/bf00400894

The oxidation process of two-phase (Ti sub 3 Al and TiAl) intermetallic compound, Ti--42 at.% Al, in air at 1073 and 1273K has been investigated. The oxidation at 1273K is much faster than that at 1073K; however, the oxidation kinetics are similar. During heating up, TiO sub 2 scale forms initially on the compound surface at approx 973K, and then Al sub 2 O sub 3 scale forms at approx 1273K. For the isothermal heating, TiO sub 2 scale slowly grows up at 1073K, while at 1273K both TiO sub 2 and Al sub 2 O sub 3 scales grow up drastically. The outer oxide scale consists of TiO sub 2 and the inner one consists of a mixture of TiO sub 2 and Al sub 2 O sub 3 . The volume of Al sub 2 O sub 3 , which forms after TiO sub 2 formation at the initial stage of oxidation, is larger at an area adjacent to the oxide/compound interface.