The Effect of Titanium Carbide and Spark Plasma Sintering Processing on Nickel–Titanium Carbide Composites

The influence of variations in the titanium carbide (TiC) content employed during spark plasma sintering (SPS) of nickel–titanium carbide (Ni-TiC) composites on its microstructure and mechanical properties has been investigated systematically. Mechanical alloying (MA) uses a technique of cold welding and repetitive fracturing of composite powder to make homogenous alloys powder. The SPS consolidates alloy powder into dense samples using joule heating at a lower temperature. Mechanical alloying was performed using a planetary high energy ball mill with 400 rpm and ball to powder ratio 15:1 for 24 h. Bulk Ni-TiC composites (with TiC content varying from 5 to 25 wt.%) consolidated via mechanical alloying followed by SPS at 65 MPa pressure and 900 °C temperature. All consolidated Ni-TiC samples exhibit significant improvement in microhardness, compression strength, and grain size due to the addition of titanium carbide (TiC) particles. The grain size of Ni reduces to approx. 40 nm from approx. 55 nm. The microhardness increases from 294 to 483 HV by increasing the weight percentage of TiC from 5 to 25.