新型钴基高温合金：成分设计、组织性能与应用进展

Novel Cobalt-Based Superalloys: Compositional Design, Microstructure-Property, and Application Progress

摘要:

传统钴基高温合金因缺乏共格强化相，其高温性能长期受限。L12型γ′-Co3(Al, W)相的发现开启了新型钴基高温合金的研究热潮。本文旨在系统综述该领域的最新进展，从成分设计、制备工艺、组织结构、力学性能及应用现状等维度进行了全面梳理。重点阐述了多元合金化与降密设计策略，结合典型案例探讨了增材制造技术在抑制偏析与裂纹方面的突破，并引入强化模型定量分析了γ′相特征参数对强度的影响。此外，深入讨论了改善合金高温氧化与热腐蚀抗力的关键机制。最后，总结了该类合金在航空发动机热端部件及高温工模具领域的应用进展，并展望了未来在解决组织稳定性与工程化制备方面的发展方向。

Abstract:

Conventional cobalt-based superalloys are limited in high-temperature properties due to the lack of coherent strengthening phases. The discovery of the L12-structured γ′-Co3(Al, W) phase has initiated the research on novel cobalt-based superalloys. This paper systematically reviews the recent progress in this field, covering composition design, processing techniques, microstructure, mechanical properties, and application status. The compositional strategies, including multi-component alloying and density reduction, are elaborated. Combined with typical cases, the breakthroughs of additive manufacturing technology in suppressing segregation and cracking are discussed. Furthermore, strengthening models are introduced to quantitatively analyze the influence of γ′ phase characteristic parameters on strength. In addition, the key mechanisms for improving high-temperature oxidation and hot corrosion resistance are deeply discussed. Finally, the application progress of these alloys in aero-engine hot-end components and high-temperature tools and molds is summarized, and future development directions regarding microstructural stability and engineering fabrication are proposed.