Ru对镍基单晶高温合金凝固特性、TCP相析出及蠕变性能影响的研究进展EI北大核心CSCD

镍基单晶高温合金因优异的高温力学性能而被广泛应用于航空发动机和地面燃气轮机的涡轮叶片等关键热端部件。Ru元素作为第四代、第五代镍基单晶高温合金的主要特征元素,其添加对合金从凝固特性到最终的服役性能都起到关键的影响。本文从镍基单晶高温合金的凝固特性、凝固组织、TCP相析出及蠕变性能等方面出发,综述了Ru元素对镍基单晶高温合金影响的研究进展,系统分析了Ru的添加对合金凝固路径、凝固特征温度、微观偏析等凝固特性及共晶、碳化物等凝固组织的影响规律,并重点探究了Ru的添加能抑制TCP相析出及提高合金蠕变性能的原因。目前由于多组元交互作用对组织与性能影响机理的复杂性,使得含Ru高温合金的成分设计与优化具有更高的挑战,建议未来含Ru高温合金的相关研究从富Ru新相的析出原因及抑制、Ru添加对凝固缺陷的影响及Ru与其他元素交互作用对“逆分配”效应及TCP相析出的影响机制等方面做进一步探究,为发展新型高性能含Ru高温合金的设计提供思路。

Research progress in effect of Ru on solidification characteristics,precipitation of topologically close-packed phases and creep property of nickel-based single crystal superalloy

Nickel-based single crystal superalloys are widely used for hot components of advanced turbine engines due to their excellent mechanical properties at elevated temperature.Ru is the symbol element of the fourth and fifth generation nickel-based superalloys.During the past decades,many efforts have been made to provide insight into the role of Ru addition in superalloys.In this paper,the research progress in the effect of Ru on the solidification characteristics,as-cast microstructures,precipitation of topologically close-packed(TCP)phases,and creep properties of nickel-based single crystal superalloy was reviewed.The effect of Ru on the solidification characteristics such as solidification path,solidification transition temperature,micro-segregation,and the solidification microstructures such as eutectic,carbide were analyzed systematically.And the reasons why the addition of Ru can inhibit the precipitation of TCP phase and improve the creep property of superalloy were emphatically studied.The composition design and optimization of Ru-containing superalloy are more challenging due to the complexity of the multi-component interaction on microstructure and properties.It was suggested that the future research on Ru-containing superalloys could be explored from the following aspects:the cause of the precipitation of the new Ru-rich phases and the method of inhibiting its precipitation,the effect of Ru addition on solidification defects,the mechanism of the interaction between Ru and other elements on the"reverse partitioning effect"and the precipitation of TCP phases.It could provide significant guidance for the composition optimization and performance improvement of the new Ru-containing nickel-based single crystal superalloys.