Recent progress in high-temperature greases: Constitutive relationships, mechanisms, and applications

In modern high-tech industries, such as aerospace, nuclear energy, and electric power, there are increasing demand for materials with high-temperature adaptability and superior lubrication properties. Grease is an essential mechanical component and widely used to reduce mechanical friction, wear and vibration. This paper comprehensively reviews of the recent progress on high-temperature grease, including design, performance indices, lubrication characteristics, developments, and applications. Starting with outlining novel insights into the relationship between composition and physic-chemical properties of high-temperature greases, as well as other factors, emphasizing the typical strategies for matrix reinforcement and high-temperature performance enhancement. The analysis gravity focuses on the intrinsic properties of high-temperature grease and the influence of working conditions on its tribological properties, leading to a detailed discussion of the lubrication mechanism. Then, the innovative fusion of high-temperature grease with new materials such as nanomaterials and ionic liquids (ILs), and interdisciplinary research involving modern emerging fields such as artificial intelligence has allowed for further progress in the development of high-temperature grease, which has a wide range of applications in aerospace components, automotive parts, and turbines are introduced. Finally, this review concludes briefly with prospects on the challenges and future directions in high-temperature grease.