Comparison of dynamic-aging creep and pre-aged creep in Ti-15-3 beta titanium alloy

Abstract

For study the high temperature application of beta titanium, all experimental creep test temperatures and the pre-aged temperature were lower than the predicted β-transus temperature (1067 K). The creep properties of the pre-aged material were superior to those of the as-received material. The activation energies of the pre-aged creep material under various test conditions were approximately twice those of the as-received material under dynamic-aging creep, even though the stress exponent of the pre-aged material was lower than that of the as-received material. Creep deformation was predominated by the diffusion mechanism. The decline in the hardness of the pre-aged creep material under an applied stress of 200 MPa was ascribed to the coarsening and degeneration of the acicular α (secondary α).