A study on the beta and omega phases in Ti-Al-Cr alloy

Journal Article · Tue Feb 15 04:00:00 EST 1994 · Scripta Metallurgica et Materialia; (United States)

DOI:https://doi.org/10.1016/0956-716X(94)90593-2· OSTI ID:5498720

Zhang, Bing; Wang, Jianguo; Wan, Xiaojing; Chen, Weijie ^[1]

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1. Shanghai Univ. of Technology (China). Inst. of Materials Science

In the early studies, only alpha-2 and gamma phases were found in this type of alloy, usually present as a lamellar mixture. The [beta] phase was recently found in some ternary TiAl alloys accompanying the addition of [beta] stabilizing elements such as Nb, Mo and Cr. This [beta] phase was considered to have a long-range ordered body centered cubic (B.C.C.) structure with a[sub 0] = 0.3197nm. This [beta] phase was also regarded as the Ti[sub 2]CrAl phase with a[sub 0] = 0.312nm. In the Ti-Al-Cr system, the [beta] phase is easy to determine owing to its higher chromium content. The omega phase is also found in a Ti-Al-Nb alloy, which has a h.c.p. structure. It has been reported that the omega phase will precipitate from the [beta] phase either during quenching or after being aged above 300 C, and that the as-quenched omega phase forms in Ti-Cr alloys with compositions between approximately 3 and 10 at% chromium. However, the precipitation of omega phase is rarely reported in Ti-Al-Cr alloys, although this phase has been found in a Ti-Al-Nb alloy. This paper is concentrated on the [beta] phase and the omega phase precipitation in a Ti-Al-Cr alloy with low aluminum content.

• OSTI ID: 5498720
• Journal Information: Scripta Metallurgica et Materialia; (United States), Journal Name: Scripta Metallurgica et Materialia; (United States) Vol. 30:4; ISSN 0956-716X; ISSN SCRMEX
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
360102* -- Metals & Alloys-- Structure & Phase Studies
ALLOY SYSTEMS
ALLOYS
ALUMINIUM ALLOYS
CHROMIUM ALLOYS
MICROSTRUCTURE
PHASE STUDIES
TERNARY ALLOY SYSTEMS
TITANIUM ALLOYS
TITANIUM BASE ALLOYS