The effect of Ti substitution by Zr on the microstructure and mechanical properties of the cermet Ti1-xZrxC sintered by SPS

Bulk novel nanocrystalline carbides Ti1-xZrxC (x = 0, 0.15, 0.20, 0.25) are prepared by mechanical alloying and spark plasma sintering (SPS). The novel carbides have good mechanical properties compared with TiC. The results showed that all alloys substituted with 0.2% Zr possessed a higher compressive strength of about 2.2 GPa than the original alloy TiC sintered without substitution. The nano-hardness of Ti1-xZrxC (x = 0, 0.15 and 0.20) hard material is 25, 23 and 28 GPa, and the modulus of elasticity 446, 370 and 422 MPa. The substitution of Ti by Zr (less than 25 wt.%) increase the optimum sintering temperature, results in reducing the grain size of the sintered samples and leads to more than 20% improvement in the studied fracture toughness. The densification behaviours and the relationship between the microstructure and the mechanical properties of the novel hard alloy are also investigated.

Figure optionsDownload as PowerPoint slideHighlights
► The limit of substitution of Ti by Zr in the Ti1-xZrxC carbide is equal to 20%.
► The carbides Ti1-xZrxC with the amount of Zr substitution of 20 wt.% exhibit a good mechanical properties.
► The mechanical behaviour of the as-consolidated material was similar to that of the brittle material.
► The MA accompanied with SPS can provide powerful tools for the fabrication of nanocrystalline carbides bulk alloys.