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In order to improve the elevated temperature mechanical properties and modify the thermophysical properties of tungsten, tungsten matrix composites containing 30 vol.% zirconium carbide particles (ZrC/W) were prepared by vacuum hot-pressing at 2000 °C. Flexural strength of ZrC/W composites increases gradually with increasing temperature and reaches a maximum value at 1000 °C. The observation of the fracture characteristics of ZrC/W composites at various temperatures reveals that the excellent elevated temperature strength is attributed to the brittle–ductile transition in the tungsten matrix, which allows a more effective strengthening effect from the zirconium carbide particles. The elastic modulus decreases slightly with increasing temperature from room temperature to 1200 °C, and as a result of the addition of zirconium carbide particles the modulus of ZrC/W is higher than that of monolithic tungsten at all testing temperatures. The addition of zirconium carbide remarkably decreases the thermal conductivity of the composites. The unique combination of high melting point, good high temperature strength, high elastic modulus, and low thermal conductivity is very beneficial to the high temperature application of ZrC/W composites. [Copyright &y& Elsevier]