Effect of Heat Treatment on the Microstructure and Mechanical Properties of Ultra-fine grained.Ti-55511 near β Titanium Alloy
The ultra-fine grained (UFG) Ti55511 near β titanium ailoy with grain size 0.1-0.5 μm was prepared by hot rolling.The effect of heat treatment on the microstructure and mechanical properties was investigated by using the methods of SEM and TEM.The results indicate that both strength and hardness are increasing firstly and then reducing with increasing heat treatment temperature from 350℃ to 650℃.The peak strength (1486.09 MPa) appears at 450℃.The strength is dramatical ly reaching to 1536MPa and then stable with in creasing the holding time when heat treated at 450℃.While the maximum dongation appears first ly increased and then decreased.The microstructure analysis shows that the dynamic recovery occurs and the grain size remains smaller than 1 μm during an nealing.The recovery stimulates the grain refine ment effect by eliminating the hardening process and stimulating the grain boundary / phase boundary to be stable.The phase transformation of α→α2 and β → ω→ α enhanced the second phase particle disper sion effect during annealing.However, the ductility of alloy could significant decrease when the second phase particles grow up to a certain size.The me chanical properties evolution during annealing are mainly related to the effect of strengthening mechanisms.
Ti-55511 alloy ultra-fine grain heat treatment microstructure mechanical property
Chao Li Xiao-yong Zhang Zhe Deng Ke-chao Zhou
State Key Laboratory of Powder Metallurgy,Central South University,Changsha 410083,China
国际会议
The 12th China-Russia Symposium on Advanced Materials and Technologies(第十二届中俄双边新材料新工艺国际会议)
昆明
英文
295-301
2013-11-19（万方平台首次上网日期，不代表论文的发表时间）