Chemical compositions of ultrafine lamellae in the water-quenched Ti-48Al alloy
- National Research Inst. for Metals, Tsukuba (Japan)
As Ti rich Ti-Al alloy shows ductile nature with the {alpha}{sub 2} + {gamma} lamellar structure, the mechanism of microstructural evolution in Ti-Al alloys has attracted much interest. Since the lamellar structure is formed by the continuous cooling in industrial processes, cooling rate dependence of {alpha} {yields} {gamma} and {alpha} {yields} {alpha}{sub 2} + {gamma} transformations has been extensively studied by many researchers. Abe et al. suggested that the ultrafine lamellae or {alpha}{sub 2} + {gamma} are formed by a displacive (martensitic) transformation without change in chemical compositions. However, in this study, they did not determine the chemical compositions in the lamellae, and no evidence to prove the displacive transformation mechanism was provided. Hence, this study aims to measure the local chemical concentration changes across the fine lamellae directly and to discuss the mechanism of microstructural evolution of the ultrafine lamellae in water-quenched Ti-48at.%Al alloy. For local concentration determination of the ultrafine lamellae, a unique microanalytical technique with an atomic spatial resolution, atom probe field ion microscopy (APFIM), was employed.
- OSTI ID:
- 271629
- Journal Information:
- Scripta Materialia, Journal Name: Scripta Materialia Journal Issue: 4 Vol. 35; ISSN 1359-6462; ISSN XZ503X
- Country of Publication:
- United States
- Language:
- English
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