Influences of HfC particles on microstructure, mechanical properties and ablation resistance at elevated temperature of Mo-15W-HfC alloys

The Mo-15W alloys with different HfC addition were prepared by using powder metallurgy technology. The effect of HfC particles on the mechanical properties and ablation resistance of Mo-15W-HfC alloys were also investigated. The results indicated that the effect of HfC particles on the Mo-W-HfC sintered alloys is very small, but it can obviously improve the micro-hardness and the ultimate tensile strength of rolled alloys. The alloy containing 1.0%wt. HfC in rolled condition delivers the highest ultimate tensile strength both at room temperature (~ 1252 MPa) and at 1250 °C (~ 500 MPa), and shows the best overall performance. The ablation tests show that the HfC particles will form an HfO2 film to prevent the Mo-15W matrix from further ablative attack at the ablation temperature.