Effect of Mo addition on the microstructure and wear resistance of in situ TiC/Al composite

In this work, Mo was investigated as an additive for in situ preparation of TiC/Al composite using a casting route assisted by self-propagating high-temperature synthesis (SHS). Experimental results show Mo improves the wettability between TiC phase and aluminium melt due to the formation of a Mo-rich shell around the formed TiC particles, which is a kind of good modificator. Compared with the composite without added Mo, 1.0 wt.% Mo addition developed finer matrix structure, significant refinement of TiC particles and more uniform distribution of TiC particles in the matrix. Meanwhile, both wear and tensile properties of TiC/Al composite were improved with 1.0 wt.% Mo addition and then deteriorated with the further increase of Mo content due to the formation of fragile phase Al5Mo.

► Mo is a kind of good modificator for TiC/Al composite.
► 1.0 wt.% is an optimal addition amount of Mo for TiC/Al composites.
► The fragile phase Al5Mo is formed with the excess Mo addition.