Ablation of tungsten matrix composites reinforced by TiC and ZrC particles

The ablation properties of tungsten matrix composites reinforced by TiC and ZrC particles (two series of TiC_p/W and ZrC_p/W) were measured with an oxyacetylene ablation equipment. Results revealed that the values of the mass ablation rate and linear ablation rate were in the order: W>30TiC_p/W>40TiC_p/W>30ZrC_p/W> 40ZrC_p/W(30TiC_p/W stands for 30% vol. content of TiC particle, the same below). The ablation surface temperature and back surface temperature of samples were successfully detected on-line by using a dynamic responding multiwavelength calorimetric pyrometer and a thermal couple, respectively. 30TiC_p/W and 40TiC_p/W failed to withstand the thermal shock of 2000°C/s during the initial stage of firing. In contrast, 30ZrC_p/W and 40ZrC_p/W withstood the thermal shock. The ablation resistance of the composites are greatly increased with addition of TiC and ZrC particles. The more is carbides content, the better is the ablation resistance. Thermal chermochemical oxidation of W, TiC and ZrC is the main ablation mechanism of the composites.