Rapid TMC laser prototyping: compositional and phase-structural sustainability via combinatorial design of titanium-based gradient alloy reinforced by nano-sized TiC or TiB2 ceramics

In this study, we developed an innovative approach to achieving a higher sustainability in the experimentally guided combinatorial design of metal-matrix gradient structural composites. The titanium carbide of nano sizes or titanium diboride of submicron sizes were incorporated into the titanium matrix during the selective laser melting (SLM) process of Ti+(10, 15, 20 wt.%) TiC/TiB₂ powder mixtures. Optimal regimes of 3D laser powder bed process were determined. We compared how the interfacial properties would change due to the composition differences in case of TiC and TiB₂ reinforcing titanium matrix composites (TMC). Phase analysis of the fabricated TMC showed that the initial TiC and TiB₂ particles dissolved with different velocities after remelting. Special attention was paid to carbon and boron dilution and secondary carbides and borides phase formation mechanisms when TiC/TiB₂ were mixed with titanium. Microstructure, phase constitution and mechanical properties of the TMCs were investigated by the OM, SEM, XRD and microhardness measurement in order to validate the rapid alloy prototyping (RAP) concept in single technological approach.