Effect of Heat Treatment on the Microstructure and Property of Metastable β Titanium Alloy

TB18 is a newly developed high-strength metastable beta-titanium alloy, commonly used in aerospace structural materials, which demands high mechanical performance. By altering the alloy's microstructure, heat treatment can affect its mechanical characteristics. The alloy was solution treated for one to four hours at 870 degrees C in order to examine the impact of solution treatment duration. Using X-ray diffraction (XRD) and scanning electron microscopy (SEM), the effects of solution treatment time on the beta-phase grain size and its effect on stress distribution during tensile testing were examined. The findings showed that stress concentration during the tensile process was successfully decreased by refining the beta-phase grain size. Sample solutions treated for two hours at 870 degrees C were then aged at various temperatures (510 degrees C, 520 degrees C, 530 degrees C, and 540 degrees C) to examine the impact of aging temperature. While the mass proportion of the alpha-phase first climbed and subsequently declined, reaching its maximum at 530 degrees C, the size of the alpha-phase increased monotonically as the aging temperature increased. The varies of mass fraction is associated with how the aging temperature affects alpha-phase nucleation. Tensile studies on TB18 alloy aged at various temperatures showed that while the alloy's ductility reduced, its strength increased as the aging temperature rose. The Hall-Petch relationship explains this tendency.