Cost-affordable and qualified powder metallurgy metastable beta titanium alloy by designing short-process consolidation and processing

Short-time processing route has been designed to manufacture cost-affordable and high-quality powder metallurgy (PM) metastable beta titanium alloy, containing rapid powder consolidation (modified thermomechanical pressing), one-step thermomechanical processing (simple open die uniaxial hot forging by industrial press) and fast heat treatment (one-step annealing at various temperatures for only one hour). Based on comprehensive microstructure characterizations and mechanical property examinations, underlying microstructural evolution mechanism and microstructure-property relationship of the produced alloys were uncovered and elucidated thoroughly. Homogeneous macrostructure and fine-grain microstructure without undissolved particles and large pores are obtained for the alloy after thermomechanical powder consolidation as a result of the concurrent effect of external deformation and high-temperature diffusion. One-step open-die forging is verified to produce full-dense and sound PM alloy pancake with large-scale and high strength. Attributed to the harmonious concurrence of hierarchical a precipitation and heterogeneous grain structure, synergistic strength-ductility combinations are achieved for the alloy after specific processing and heat treatment with the tensile strength and strain at failure values of 1386.5 MPa/7.3% and 1252.3 MPa/9.0%, respectively. These strength-ductility combinations are comparable and/or even better than other metastable beta titanium alloys prepared by some PM and ingot metallurgy approaches with relatively high cost and time consumption. (C) 2021 The Author(s). Published by Elsevier Ltd.

Automated summary

A short-time processing route has been designed to manufacture cost-affordable and high-quality powder metallurgy (PM) metastable beta titanium alloy, achieving homogeneous macrostructure and fine-grain microstructure. The alloy demonstrates synergistic strength-ductility combinations after specific processing and heat treatment, with comparable or even better performance than other alloys prepared by traditional methods.