ANOMALOUS STRAIN RATE DEPENDENCE OF FLOW STRESS IN TiAl INTERMETALLIC COMPOUNDS
WANG Liming;ZHU Dong;YAO Mei;CAI Qigong;ZOU Dunxu State Key Laboratory for Fatigue and Fracture of Materials; Academia Sinica; Shenyang; Central Iron and Steel Research Institute; Ministory of Metallurgical Industry; Beijing
Cite this article:
WANG Liming;ZHU Dong;YAO Mei;CAI Qigong;ZOU Dunxu State Key Laboratory for Fatigue and Fracture of Materials; Academia Sinica; Shenyang; Central Iron and Steel Research Institute; Ministory of Metallurgical Industry; Beijing. ANOMALOUS STRAIN RATE DEPENDENCE OF FLOW STRESS IN TiAl INTERMETALLIC COMPOUNDS. Acta Metall Sin, 1992, 28(4): 40-44.
Abstract Plastic deformation of TiAl and TiAl-V intermetallic compounds has been stu-died by compression experiment at various temperatures and strain rates. Results show that theplastic deformation in distinct temperature range is principally controlled by the mechanisms ofPerierls-Nabarro, cross slip and creep of dislocation. For TiAl-V alloy deformed at a range of600--700 K, the negative strain rate dependence of flow stress was observed, i. e., the more theplastic strain is, the more the negative dependence will be. A possible mechanism of the anomalycould be interpreted by thermal activation of dislocation cross slipping. The effects of tempera-ture and strain rate on work-hardening exponent were also studied and discussed.
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