Structure Formation during High-Temperature Synthesis in an Activated Ti + Al Powder Mixture

Abstract

This paper presents a detailed experimental study of phase formation processes in a mechanically activated Ti + Al powder mixture. High-temperature synthesis has been performed in thermal explosion mode using induction heating of the mixture. We present the first evidence that, during a continuous transition from rapid heating to high-temperature annealing, the composition of the synthesis products depends on the secondary structuring time. Early stages of annealing involve structural relaxation processes, which make the phase composition more uniform and lead to the formation of an essentially single-phase TiAl compound. In later stages, the system undergoes a transition to thermodynamic equilibrium, which is accompanied by the formation of compounds that are in equilibrium at the annealing temperature.