The phase and microstructure of TC21 alloy

TC21 alloy is a new alpha–beta damage tolerance titanium alloy with high strength and high toughness. Little work has been done in the field of microstructure and phase analysis since this alloy was developed. The phase and microstructure of TC21 alloy under different heat-treatment were investigated in this paper. Different experiment methods such as OM, SEM, TEM and XRD were adopted to investigate the microstructure and phase of TC21. The result showed that heat-treatment parameters (solution temperature, cooling rate and cooling mode) had influence on the feature of α phase, β phase and secondary α phase. Two precipitated phases (α2-Ti3Al and B2-Ti2AlNb) were discovered by XRD analysis.