Microstructure and mechanical properties of W-Cr-TiN composite by spark plasma sintering

W-x wt.% Cr-3 wt.% TiN (x = 0, 2, 4) composites were fabricated by mechanical alloying (MA) with spark plasma sintering (SPS). A homogenous composite powder with small crystallite sizes was obtained by MA for 30 h. Cr and TiN homogeneously distributed in W matrix when the MA powder was sintered at 1450 °C, while most Cr and Ti aggregated together at sintering temperature of 1750 °C and most N elements were lost. Thermodynamic analysis showed that the dissolution of Cr into TiN to form (Ti,Cr)N solid solution, which causes the content of N element decreasing and Cr-rich phase gradually disappearing at higher sintering temperature. The effect of Cr content on the microstructure and mechanical properties of W composites was also studied. Relative density, Vickers hardness and elastic modulus are positively correlated with the increase of Cr content. W-4Cr-3TiN has the most excellent performance with 99.3% relative density, 825 HV10Kg, and 243 GPa elastic modulus.