Abstract
In this study, we proposed a novel method for in-situ additive manufacturing of TiC reinforced Ti6Al4V-matrix functionally graded composite materials (FGMs) based on gas–liquid reaction. Laser-induced pyrolysis of methane gas (CH4) near the surface of the Ti6Al4V melt pool provides carbon atoms/ions which react with titanium atoms to in-situ synthesize TiC reinforcements. Clean interface and excellent dispersion between the TiC reinforcement and Ti matrix were achieved owing to in-situ gas–liquid reaction, good diffusivity and dispersibility of the gaseous carbon source. As anticipated, spatially varying volume fraction and grain size of the TiC reinforcement, continuously varying microhardness and wear resistance were attained in the TiC/Ti6Al4V FGM by controlling continuous variation of CH4 concentration.
NSTL
Elsevier