Static coarsening behavior of equiaxed α phase in Ti-8Al-1Mo-1V alloy
(1. College of Materials Science and Engineering, Taiyuan University of Technology, Taiyuan 030024, China;
2. Erich Schmid Institute of Materials Science, Austrian Academy of Sciences, LeobenA-8700, Austria;
3. Department of Materials Science, Chair of Materials Physics, Montanuniversit？t Leoben, LeobenA-8700, Austria)
2. Erich Schmid Institute of Materials Science, Austrian Academy of Sciences, LeobenA-8700, Austria;
3. Department of Materials Science, Chair of Materials Physics, Montanuniversit？t Leoben, LeobenA-8700, Austria)
Abstract: To get a deep understanding of the evolution behavior of equiaxed α phase in Ti-8Al-1Mo-1V alloy during annealing, its static coarsening mechanism was studied based on the calculations of coarsening exponent n and the activation energy for α boundary migration. The result of n=6 indicates a special coarsening mechanism of equiaxed α phase. The activation energy for α boundary migration is calculated to be 138 kJ/mol, which is close to the activation energy for grain growth of pure α-Ti. It is revealed that the coarsening of equiaxed α can be mainly attributed to the self-diffusion of Ti atoms across the α/α boundaries. Based on the experimental findings, a static coarsening kinetics model of equiaxed α grains in the α+β field is established. At last, the effects of the coarsening behavior of equiaxed α on tensile properties were studied.
Key words: static coarsening; kinetics; model; tensile properties; Ti-8Al-1Mo-1V