In this paper, to solve the problem that di‐n‐hexadecyldithiophosphate (DDP)‐modified Cu nanoparticles initially used as oil‐based lubricant additive cannot be directly used in water‐based lubricants, we adopt a water‐in‐oil reverse micro‐emulsion method to incorporate hydrophobic Cu nanoparticles into silica spheres for obtaining water‐dispersible Cu@SiO₂ nanoparticles. The effects of reaction conditions on the morphology and microstructure of Cu@SiO₂ nanoparticles were investigated. Furthermore, the tribological properties of the as‐prepared Cu@SiO₂ nanoparticles as a lubricant additive in distilled water were investigated with a UMT‐2MT tribometer. Results indicate that the as‐prepared Cu@SiO₂ nanoparticles exhibit good dispersion stability and antioxidant ability in distilled water. Besides, Cu@SiO₂ nanoparticles can significantly improve the tribological properties of distilled water, which is attributed to the formation of a protective and lubricious film consisting of Cu, FeS and SiO₂ on the rubbed steel surface.

中文翻译：

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Cu @ SiO2复合纳米粒子的制备及其作为水基润滑剂添加剂的摩擦学性能

在本文中，为解决最初用作油基润滑剂添加剂的二正十六烷基二硫代磷酸二甲酯（DDP）改性的Cu纳米颗粒不能直接用于水基润滑剂的问题，我们采用油中水反向微粉化技术。乳液法将疏水性Cu纳米粒子掺入二氧化硅球中以获得水分散性Cu @ SiO ₂纳米粒子。研究了反应条件对Cu @ SiO ₂纳米粒子的形貌和微观结构的影响。此外，使用UMT-2MT摩擦计对制备的Cu @ SiO ₂纳米颗粒作为润滑剂在蒸馏水中的摩擦性能进行了研究。结果表明，所制备的Cu @ SiO ₂纳米颗粒在蒸馏水中表现出良好的分散稳定性和抗氧化能力。此外，Cu @ SiO ₂纳米颗粒可以显着改善蒸馏水的摩擦学性能，这归因于在摩擦的钢表面上形成了由Cu，FeS和SiO ₂组成的保护性润滑膜。