Interdiffusion in β phase of the ternary Ti-Al-V system

Abstract

The interdiffusion in Ti-rich β Ti-Al-V alloys has been investigated in the temperature range from 1323 to 1473 K. The direct interdiffusion coefficients, D̃ AlAlTi and D̃ VVTi, and indirect interdiffusion coefficients, D̃ AlVTi and D̃ VAlTi, are positive in the ternary alloys, and these four interdiffusion coefficients have slight concentration dependence. The values of D̃ AlAlTi are larger than those of D̃ VVTi, and the values of D̃ AlVTi are also larger than those of D̃ VAlTi. The repulsive interactions exist between Al and V atoms in the Ti-Al-V alloys, because the ratio values of indirect coefficient to direct one are positive. On the other hand, the interactions between Ti (solvent) and Al (or V) atoms are attractive in the present alloy, since the ratio of converted interdiffusion coefficients in the ternary alloys shows negative values. © 2008 The Japan Institute of Metals.