Microstructure and tribological behavior of in situ synthesized (TiB+TiC)/Ti6Al4V (TiB/TiC=1/1) composites

Abstract

To enhance wear properties of titanium alloys, in situ titanium matrix composites (TMCs) were synthesized by a melting cast method with (TiC + TiB) volume fractions of 0, 2, 4, 6, 8, and 10%. The results indicated that tribological properties of TMCs were increased owing to the dispersed distribution of (TiC + TiB) reinforcements, which improved the ability to resist the surface shear stress. Moreover, the stable transfer layer formed during wear reduced the shear strength and limited the direct interaction at tribo-pair interfaces to enhance surface hardness and wear resistance effectively. Consequently, the wear mechanism appeared to transitioned from the severe adhesive and oxidative wear gradually to the slight adhesion, abrasive, and oxidative wear along with reinforcements content increased.