激光增材制造NbTiMoVHf(Zr)Six六元高熵合金的成分设计与成形机理

Ultrahigh-temperature structural material has always been a research focus in the field of material. In order to solve the technical barrier of the insufficient room-temperature fracture toughness of Nb-Si based refractory alloy, research on additive manufacturing of ultrahigh-temperature structural material from the perspective of multicomponent high entropy alloy is proposed in this project, to achieve good match between room-temperature fracture toughness and high temperature (1200~1400 ℃) strength..The key scientific problems to be solved: Design the system and composition of multicomponent alloy, obtain the formation condition of high entropy stable solid solution structure, and promote the precipitation of Nb5Si3 high melting point reinforcement in the multicomponent solid solution matrix, so as to realize the microstructure control of the alloy and reveal its mechanism..The main research contents: Composition design of high entropy alloy, laser melting deposition experiment and forming mechanism, microstructure analysis and alloy composition optimization, mechanical properties evaluation and fracture mechanism, as well as formation condition and control mechanism of multi-component high entropy stable solid solution structure and Nb5Si3 reinforcement..Exploration research of high entropy alloy ultrahigh-temperature structural material potentially with good room-temperature toughness and high-temperature performance will be carried out in the project. The microstructure feature, formation mechanism and control method of laser melting deposited multicomponent high entropy stable solid solution will be revealed and the basic theory of laser additive manufacturing high-temperature high entropy alloy will be formed. This project is of important significance of scientific research and engineering application prospect.

超高温结构材料一直是材料界的研究热点。为解决Nb-Si基难熔合金室温韧性不足的技术障碍，本项目提出从研究多元高熵合金的角度，进行超高温结构材料的激光增材制造研究，实现室温断裂韧性和高温（1200~1400℃）强度的良好匹配。.关键科学问题：设计多元合金体系与成分，获得高熵稳定固溶体结构的形成条件，并促成多元固溶体基体上析出Nb5Si3高熔点增强相，实现对合金微观组织的调控，并揭示其机理。.主要研究内容：高熵合金成分设计；激光熔化沉积实验和成形机理；微观组织分析与合金成分优化；力学性能评价与断裂机理；多元高熵稳定固溶体结构及Nb5Si3增强相的形成条件与调控机理。.本项目将对有潜力兼具优异室温韧性和耐高温性能的高熵合金超高温结构材料开展探索研究，揭示激光熔化沉积制备多元高熵稳定固溶体的组织特征、形成机理和调控方法，形成激光增材制造耐高温高熵合金的基础理论，具有重要科学研究意义和工程应用前景。

超高温结构材料一直是材料界的研究热点，为解决现有高温材料力学性能不足及难成形的技术障碍，本项目针对有潜力兼具优异室温韧性和耐高温性能的高熵合金超高温结构材料开展探索研究，首先开展了多元高熵合金体系的成分设计工作，获得了高熵稳定固溶体结构的形成条件，并促成多元固溶体基体上析出高熔点增强相，然后对上述新型高熵合金进行了力学性能评价与断裂机理分析；进一步通过激光熔化沉积实验进行了成形测试，分析了成形机理和微观组织结构；揭示了新型多元高熵稳定固溶体的组织特征、形成机理和调控方法，为激光增材制造耐高温高熵合金提供了材料储备与理论支持。