Machinability of TiC-reinforced titanium matrix composites fabricated by additive manufacturing

Additive manufacturing (AM) of TiC particle-reinforced titanium matrix composites (TiC-TMCs) has promising applications in aircraft and aerospace, attributed to its advantages of near-net shaping for AM and the excellent mechanical properties for TiC-TMCs. However, the surface quality of AM produced parts is inferior to that of the conventionally formed parts. This study investigated the machinability for TiC-TMCs specimens prepared by AM. The microstructural characteristics of TiC after AM were analyzed. The effects of the microstructure on cutting force, machined surface morphology, chip formation, and tool wear were studied. The results showed that a varied set of AM parameters caused a different microstructure and thus different machinability of TiC-TMCs. Compared to the specimens with coarse dendritic TiC, the fine equiaxed TiC possessed better machined surface quality and lower tool wear and thus better machinability. This study is expected to further exploit the advantages of AM and promote precision manufacturing of TiC-TMCs parts.