中国有色金属学报(英文版)
Transactions of Nonferrous Metals Society of China
| Vol. 12 No. 4 August 2002 |
Site occupations and ordering behaviour of
O phase in Ti2AlNb-based intermetallics
O phase in Ti2AlNb-based intermetallics
（1. General Research Institute for Non-ferrous Metals, Beijing 100088, China;
2. State Key Laboratory for Precision Hot Processing of Metals,
Harbin Institute of Technology, Harbin 150001, China）
Abstract:The site occupations of the alloying elements of O phase in Ti2AlNb-based intermetallics are clarified. The ordering behaviours of the O phase in Ti-yAl-zNb(y≥25%, mole fraction) orthorhombic alloys are also investigated with a Bragg-Williams model. In the temperature range where the O phases exist, the order parameters change with the alloy composition and temperature continuously, and the first-order transition character is very “weak” .
Key words: Ti2AlNb-based intermetallics；orthorhombic phase；site occupation；ordering behaviour
