Effect of Structural and Phase State on the Creep of an Ultrafine-Grained Ti–Al–V–Mo Titanium Alloy

Abstract

The effect of the phase composition on the regularities of creep of the ultrafine-grained Ti–Al–V–Mo titanium alloy at the temperature of 723 K and in the range of strain rates from 10^–7 to 10^–5 s^–1 has been studied in this work. It has been found that the formation of the nonequilibrium phase composition in the ultrafine-grained alloy leads to a violation of the power law of creep. It has been shown that this violation is associated with the development of the β → α phase transformation during creep and with the redistribution of alloying elements. The physical causes of a decrease in the effective energy of activation of the creep of the alloy with ultrafine-grained structure and nonequilibrium phase composition have been discussed.