Effect of doped niobium on the microstructure and properties of W–Nb/TiC composites prepared by spark plasma sintering

• W–Nb/TiC composites were synthesized by machine milling and spark plasma sintering.
• Effect of Nb on the microstructure and properties of W–TiC were investigated.
• The performance of W–1 wt%Nb–1 wt%TiC was better than that of W–1 wt%TiC.

W–1 wt%Nb/TiC composites were prepared by mechanical milling and spark plasma sintering. Field-emission scanning electron microscopy, high-resolution transmission electron microscopy, and thermal conductivity analyses were used to characterize the samples. Results showed that niobium carbide (NbC) formed in the composites. The relative density of the composites has been improved after adding Nb into W–1 wt%TiC. The tensile strength increased as well because Nb has high affinity for impurities such as O, C, and N and can form with these elements hard compounds. The thermal conductivity of W–1 wt%Nb/TiC was also improved, in comparison with that of W–1 wt%TiC.