中國有色金屬學(xué)報(英文版)
Transactions of Nonferrous Metals Society of China
| Vol. 8 No. 2 June 1998 |
（State Key Laboratoryfor Advanced Metals and Materials, Department of Materials Science and Engineering, University of Science and Technology Beijing,Beijing100083, P. R. China）
Abstract:Strain induced structure transition (SIST) during hot deformation in TiAl alloy was investigated by high-resolution transmission electron microscopy(TEM). Various non-equilibrium asymmetrical twin boundaries with a large number of ledges were found. Special non-equilibrium tilt and asymmetricalγ/αinterfaces were also illustrated. The normal crystal relation betweenγandαcan be changed. The 1/3[111] Frank partial dislocations often appear at these non-equilibrium interfaces. It was also reported that the strain induced phase transitions, includingγ→α,α→γandγ→9Rstructure, commonly occur during hot deformation; the strain induced phase transitions are closely related to interface structure. The dislocation reactions and mechanisms for SIST were discussed.
Key words: TiAl alloy strain induced structure transition phase transformation interfacial structure
