New Ablation-Resistant Material Candidate for Hypersonic Applications: Synthesis, Composition, and Oxidation Resistance of HfIr3-Based Solid Solution.

The peculiarities of the solid-state interaction in the HfC-Ir system have been studied within the 1000-1600 °C temperature range using a set of modern analytical techniques. It was stated that the interaction of HfC with iridium becomes noticeable at temperatures as low as 1000-1100 °C and results in the formation of HfIr3-based substitutional solid solution. The homogeneity range of the HfIr3± x phase was evaluated and refined as HfIr2.43-HfIr3.36. The durability of the HfIr3-based system under extreme environmental conditions was studied. It was shown that the HfIr3-based material displays excellent ablation resistance under extreme environmental conditions. The benefits of the new designed material result from its relative oxygen impermeability and special microstructure similar to superalloys. The results obtained in this work allow us to consider HfIr3 as a very promising candidate for extreme applications.