Abstract The simple hot press assisted synthesis of iridium-based intermetallics, MIr3±x, (M = Hf, Ta) from the powder mixtures of corresponding carbides and iridium, and the powder mixtures of the metal and iridium was proposed. The application of pressure provides the formation of dense intermetallic MIr3±x phase as the main constituent. The coefficient of thermal expansion (CTE) of the TaIr3 phase was determined by means of high-temperature X-ray diffraction analysis. The CTE was evaluated to be equal to 5.2∙10−6 K−1. A set of thermophysical properties, such as spectral emissivity, linear expansion of the sample, heat capacity, thermal diffusivity, and thermal conductivity of the TaIr3-based intermetallic material were determined using the original laser-flash technique up to 2200 K. The effect of porosity and composition on the thermal conductivity of the TaIr3-based material is discussed. The results can be of interest for the evaluation of the behavior of the TaIr3-based intermetallic material at ultra-high temperatures.

中文翻译：

---

铱金属间化合物的热压辅助合成及热物理性能

摘要 提出了从相应的碳化物和铱的粉末混合物以及金属和铱的粉末混合物中简单的热压辅助合成铱基金属间化合物MIr3±x, (M = Hf, Ta)。压力的应用提供了作为主要成分的致密金属间化合物 MIr3±x 相的形成。TaIr3 相的热膨胀系数 (CTE) 通过高温 X 射线衍射分析确定。CTE 被评估为等于 5.2∙10−6 K−1。使用高达 2200 K 的原始激光闪光技术确定了一系列热物理特性，例如光谱发射率、样品的线性膨胀、热容、热扩散率和基于 TaIr3 的金属间材料的热导率。讨论了孔隙率和成分对 TaIr3 基材料热导率的影响。该结果可用于评估 TaIr3 基金属间材料在超高温下的行为。