Effect of power spinning and heat treatment on microstructure evolution and mechanical properties of duplex low-cost titanium alloy

The microstructural evolution and mechanical properties of low-cost Ti-5.5Al-1Fe-3.5Cr-3.2Zr-0.2Si al-loy during power spinning and after three types of heat-treatment routines (low-temperature anneal-ing, high-temperature annealing, solution and annealing) were systematically studied. An effective heat -treatment routine to fabricate high-strength and acceptable ductile as-spun Ti-5.5Al-1Fe-3.5Cr-3.2Zr-0.2Si alloy tubes was then proposed whereby the relationship between the mechanical performances and mi-crostructures was analyzed. The {0 0 02}alpha and {0 01}beta textures were formed after multi-pass power spin-ning. The as-spun LC-Ti alloy exhibited a good combination of strength and elongation after heat treat-ment at 550 degrees C for 4 h, which was ascribed to the large plastic induced low-temperature spheroidization of deformed alpha phase and nanoscale alpha precipitation from deformed beta phase. However, the elongation de-creased evidently when Zr2Si/TiCr2 participated at the interphase boundaries after heat treatment at 550 degrees C for 8 h. In high-temperature annealing, the elongation changed nonlinearly owing to the precipitation of Zr2Si particles at triangular grain boundaries treated at 750 degrees C for 1 h, and the spheroidization of the deformed alpha(p) phase. Under solution and annealing conditions, lenticular alpha s would participate from the metastable beta grains, which contributed to the greatest strength albeit poor ductility. This study provides an effective guidance for the processing and application of the low-cost titanium alloy. (C) 2022 Published by Elsevier Ltd on behalf of The editorial office of Journal of Materials Science & Technology.