The {gamma} {r_arrow} {alpha} phase transformation in {gamma}-based TiAl alloy

Journal Article · Mon Jan 15 04:00:00 EST 1996 · Scripta Materialia

DOI:https://doi.org/10.1016/1359-6462(95)00513-7· OSTI ID:186795

Kumagai, T; Abe, E; Kimura, T; Nakamura, M ^[1]

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1. National Research Inst. for Metals, Tsukuba, Ibaraki (Japan)

The mechanical properties of {gamma}-TiAl based alloys are very sensitive to the microstructure, so that it is important to understand the phase transformation in this alloys. The microstructure developed through the {alpha} {r_arrow} {gamma} phase transformation is widely changed from a fully lamellar structure, through a fine lamellar structure with Widmanstaetten-type morphology, to a massively transformed {gamma} structure with an increase in cooling rate from the high-temperature {alpha}-Ti phase field. However, the recent study revealed that the {alpha} {r_arrow} {gamma} massively transformation is partially suppressed by the long-time solution treating prior to rapidly quenching, and the untransformed region consisting of extremely fine {alpha}{sub 2}-Ti{sub 3}Al/{gamma} lamellae, which are quite different from the lamellae due to diffusional transformation, is formed. In this study the microstructural observations of the short- and long-time aging samples are conducted in a Ti-51 at.%Al alloy and the {gamma} {r_arrow} {alpha} phase transformation is discussed.

• OSTI ID: 186795
• Journal Information: Scripta Materialia, Journal Name: Scripta Materialia Journal Issue: 2 Vol. 34; ISSN 1359-6462; ISSN XZ503X
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
AGING
ALUMINIUM ALLOYS
CHEMICAL COMPOSITION
CRYSTAL-PHASE TRANSFORMATIONS
DIFFUSION
HEAT TREATMENTS
INTERMETALLIC COMPOUNDS
LAMELLAE
MARTENSITE
MORPHOLOGY
QUENCHING
SAMPLE PREPARATION
TITANIUM ALLOYS