| Title |
High-Temperature Deformation Behavior of ELI Grade Ti-6Al-4V Alloy Having Uniformly Distributed Beta-Phase |
| Authors |
박찬희(Chan Hee Park); 고영건(Young Gun Ko); 이종수(Chong Soo Lee) |
| ISSN |
1738-8228(ISSN), 2288-8241(eISSN) |
| Keywords |
ELI grade Ti-6Al-4V; Beta-phase; Superplasticity; Strain rate sensitivity; Activation energy |
| Abstract |
High-temperature deformation behavior of extra-low interstitial Ti-6Al-4V alloy with initially equiaxed microstructure (d = 5 μm) was investigated with the variations of temperature and strain rate in this study. Thin striped beta-phase of the starting material was uniformly distributed throughout the microstructure by imposing beta-annealing followed by hot cross-rolling processes (ε = 1). A series of uni-axial tension tests was carried out at temperatures of 800℃ to 950℃ and strain rates of 10(-4) s(-1) to 10(-2) S(-1). The tension tests evidenced that the present samples showed significantly higher elongation as compared to conventional ELI grade Ti-6Al-4V alloy at the same temperature and strain rate. It was mainly attributed to increased alpha/beta interface area resulting from the breakdown of beta-phase. A total elongation-to-failure of 1898% was obtained at temperature of 850℃ and strain rate of 10(-3) S(-1). In addition, a predominant deformation mechanism operating at high-temperature was suggested by using both microstructure and activation energy. |