Conductive TiC/Ti-Cu/C composites fabricated by Ti-Cu alloy reactive infiltration into 3D-printed carbon performs

The microstructure and electrical properties of dense TiC/Ti-Cu/C composites fabricated by pressureless reactive infiltration of Ti-Cu alloy into porous starch-derived carbon preforms prepared by 3D printing was evaluated. Porosities in the range of 65-78vol% were varied by post-isostatic pressing the as-printed preforms at pressures of 50-400MPa. The reactive melt infiltration was carried out at 1100? in a flowing Ar atmosphere and resulted in formation of a composite comprised predominantly of substoichiometric TiC, binary intermetallic Ti-Cu phases and residual carbon. Scanning electron microscopy analyses revealed a microstructure consisting of dispersed fine-grained TiC in a Ti-Cu matrix surrounded by a continuous carbon phase. Electrical resistivity measurements using the four-probe method were carried out and correlated to the composite microstructure. The electrical resistivity was evaluated in terms of carbon and TiC volume fractions.