Evolution of microstructure and mechanical properties of cold-rolled Ti-34Nb-(0, 0.3, 0.6)O alloys during aging

• Published in: Journal of materials science 2022-10, Vol.57 (40), p.19088-19106
• Main Authors: Wu, Xiangwei, Zou, Wenqian, Huang, Jindu, Chen, Feng
• Format: Article
• Language: English
• Subjects: Aging (metallurgy); Alloys; Analysis; Characterization and Evaluation of Materials; Chemistry and Materials Science; Classical Mechanics; Cold rolling; Crystallography and Scattering Methods; Degassing of metals; Elastic properties; Elongation; Materials Science; Mechanical properties; Metals; Metals & Corrosion; Microstructure; Modulus of elasticity; Oxygen enrichment; Phase transitions; Polymer Sciences; Solid Mechanics; Specialty metals industry; Spheroidizing; Strain; Surgical implants; Titanium base alloys; Transformation temperature
• ISSN: 0022-2461; 1573-4803
• DOI: 10.1007/s10853-022-07756-x

This study investigated the effects of O content on microstructure and mechanical properties of cold-rolled Ti-34Nb-(0, 0.3, 0.6)O (wt.%) alloys during aging within a wide temperature range (300 °C ~ 550 °C) by means of TMA, XRD, TEM and SEM. With the increase of aging temperature, it is found that: (1) O suppresses the precipitation of ω phase, thereby delaying the precipitation of α phase, and increases the precipitation peak temperature of α phase; (2) O inhibits the growth, spheroidization and decomposition of α phase, and increases the ( α  +  β )/ β phase transformation temperature; (3) at the same aging temperature (400 °C ~ 550 °C), oxygen-enriched alloys have higher strength and elastic properties. The elastic allowable strain ( σ 0.2 /E) of Ti-34Nb-(0.3, 0.6)O alloys after aging at 400 °C × 8 h is up to 1.8%, which makes them suitable for preparing heat-resistant and high-elastic components for aerospace field. Ti-34Nb-0.3O alloy after aging at 450 °C × 8 h exhibits lower elastic modulus, high strength and good elongation, and has a good application prospect in the field of human implant materials.