The Range of the Occurrence of α Phase in near β Titanium Alloys

Abstract

Two near β titanium alloys (Ti-3Al-8V-6Cr-4Mo-4Zr and Ti-10V-2Fe-3Al) were investigated in his research. Both materials contained disperse precipitations of α phase in β phase matrix. In the case of Ti-3Al-8V-6Cr-4Mo-4Zr alloy clear segregation of alloy constituents, resulting from casting process, were observed. This segregation caused different susceptibility to α phase precipitation in dendritic and interdendritic areas in the microstructure of the investigated alloy. The influence of the temperature, strain and processing time on α phase dissolution was determined. Gleeble compression tests were performed on both of the investigated alloys. The research showed different character of the influence of strain rate and processing time on the temperature of α phase dissolution for each alloy. The effect of heat treatment on α phase dissolution during ageing of the investigated alloys was also determined. The possibility of obtaining homogenous microstructure in these alloys by properly designed heat treatment was also discussed.