中国有色金属学报(英文版)
Transactions of Nonferrous Metals Society of China
Vol. 14 No. 4 August 2004 |
(1. School of Materials Science and Engineering, Central South University, Changsha 410083, China;
2. Department of Mechanical Engineering and Intelligent Systems,
University of Electro-Communications, Japan)
Abstract:The microstructure evolution mechanism in adiabatic shear band in commercial pure titanium (TA2) at high strain rates(γ≈105106/s) were studied. The nanosized recrystallized grains (about 50 nm in diameter) within the center of adiabatic shear band (ASB) were observed by means of transmission electronic microscope (TEM). A Rotational Dynamic Recrystallization (RDR) mechanism can explain the microstructure evolution (i.e. nanosized grains were formed
within 5-10μs) in ASB. Kinetics calculations indicate that the recrystallized small grains are formed during the deformation and don t undergo significant growth by grain boundary migration after deformation.
Key words: adiabatic shear band; microstructure evolution; dynamic recrystallization