Effect of the Distribution State of Carbide on Microstructure of Ti-25V-15Cr-2Al-0.2C-x Alloys

Abstract:

Carbide and phase are two main precipitation phases in the matrix of Ti-25V-15Cr-2Al-0.2C-x(x=0, 2%Mo, 2%Nb, etc) non-burning titanium alloys. The heat treatment and thermal exposure microstructure of the alloys with different distribution state of carbide has been investigated using optical microscope (OM), scanning electron microscope (SEM) and transmission electron microscope (TEM). The results show that carbide particles with smaller sizes and higher dispersity can not only refine the microstructure of the alloys, but also significantly suppress the formation of precipitates which are detrimental to the microstructural stability of the alloys. The smaller the size and the more uniform the distribution of carbide, the stronger the effect of suppressing precipitatesthus the better microstructural stability of the alloys will be obtained.