Abstract

This paper presents an in-depth study on the combustion synthesis, solid-solution formation, processing, and characterization of NbB₂–HfB₂ ceramics, aiming to explore their potential applications, particularly in industries requiring high-performance materials. We conducted macrokinetic measurements and fitted regression models to predict combustion temperature and velocity for compositions ranging from 50 to 100% HfB₂. A combined method of ball milling and hot pressing was developed for processing the combustion products into dense ceramics. These methods resulted in samples with relative densities reaching 97%, hardness of up to 34 GPa, and Young’s modulus of up to 530 GPa, with NbB₂–50% HfB₂ solid solution exhibiting the best mechanical properties. The study revealed a linear increase in thermal properties and density with the rise in HfB₂ content. The thermal conductivity of the solid solutions in the Nb–Hf–B system ranged from 34 to 40 W/mK and was found to increase with temperature, making these ceramics suitable for ultra-high-temperature applications. The findings have significant implications for aerospace and high-performance engineering sectors and provide a solid foundation for further investigation of Nb–Hf–B ceramics under real-world operational conditions.

中文翻译：

---

超高温 NbB2–HfB2 固溶体的燃烧合成与表征

摘要

_{本文对NbB 2} –HfB ₂陶瓷的燃烧合成、固溶体形成、加工和表征进行了深入研究，旨在探索其潜在应用，特别是在需要高性能材料的行业中。我们进行了宏观动力学测量并拟合了回归模型来预测 50% 至 100% HfB ₂成分的燃烧温度和速度。开发了球磨和热压的组合方法，将燃烧产物加工成致密陶瓷。这些方法得到的样品相对密度达到97%，硬度高达34 GPa，杨氏模量高达530 GPa，其中NbB ₂ –50% HfB ₂固溶体表现出最佳的力学性能。研究表明，随着 HfB ₂含量的增加，热性能和密度呈线性增加。 Nb-Hf-B 系统中固溶体的热导率范围为 34 至 40 W/mK，并且随着温度的升高而增加，使得这些陶瓷适合超高温应用。这些发现对航空航天和高性能工程领域具有重大影响，并为在实际操作条件下进一步研究 Nb-Hf-B 陶瓷提供了坚实的基础。