镍纳米微粒的控制合成及其作为菜籽油基酯类润滑油添加剂的摩擦学机制研究

The performance of lubricating oil products is highly dependent on the properties of the lubricant base stocks and additives as well as the compatibility between the base stocks and additives. This is why great efforts have been continuously made to develop novel lubricant oil base stocks and additives as well as to study the law of compatibility between the lubricant base stocks and additives. Nanoadditive is a new kind of high-performance additive, while vegetable-based ester oil with desired biodegradability is one of the frontiers in the field of lubricant base stocks. However, currently the extreme lack of the research on the micro-tribological mechanism of nanoadditives and on the law of compatibility between lubricant base stocks and nanoadditives has seriously restricted the development of the next generation high-performance biodegradable lubricating oil. Therefore, this proposal is to design and synthesize oil soluble Ni nanoparticles with different morphology so as to get rid of the competitive adsorption of conventional lubricant additives and vegetable oil-based base stocks on the sliding surfaces of frictional pair through the introduction of magnetic Ni nanoparticles. Furthermore, it is to study the effect of the morphology of as-synthesized Ni nanoparticles on their tribological performance and to reveal the correlation between the microstructure of the as-synthesized Ni nanoparticles and their tribological properties as well as the micro-tribological mechanism of the nanoadditives. The present research, hopefully, is to accumulate fundamental data and establish theoretical reference for the development of high-performance nanoadditives suitable for ester-type lubricant base stocks.

新型润滑添加剂和基础油以及二者之间配伍规律的研究始终贯穿于高性能润滑油的研发。而纳米添加剂作为一类新兴高性能添加剂，同时具有良好可生物降解性的植物基酯类油则是目前润滑基础油研究的前沿之一。但目前对纳米添加剂微观摩擦学机制和其与植物基润滑油配伍规律研究的欠缺严重制约了我国下一代可生物降解高性能润滑油的研发。本项目针对这两个问题，设计合成具有不同形貌的油溶性Ni纳米微粒，利用Ni纳米微粒的磁性解决传统添加剂与植物基润滑基础油在摩擦副表面竞争吸附的难题。通过研究Ni纳米微粒微观形貌对其摩擦学性能的影响，阐明纳米添加剂的微观摩擦学机制，揭示纳米添加剂微观结构与摩擦学性能的关系规律，为发展酯类油用高性能纳米添加剂提供理论指导和基础数据。

本项目通过热分解、溶胶凝胶法和原位表面修饰技术等设计合成了不同形貌的Ni纳米材料和不同粒径的SiO2颗粒。实现了粒径、组分及形貌的控制制备，利用修饰剂分子中的功能基团与纳米微粒的强相互作用（化学键）赋予纳米微粒良好的化学稳定性。系统研究了Ni纳米微粒的形貌对摩擦学性能的影响，深入探讨了镍纳米微粒原位催化形成的碳基摩擦膜的微观结构，提出了镍和氧化镍嵌入无定形碳膜形成类混凝土结构的复合摩擦膜，具有优异的高负荷和低摩擦性能；在磁场控制条件下，在摩擦接触区沉积的镍纳米微粒原位催化在摩擦表面上形成了多层复合结构的摩擦膜，从而改善了润滑油的摩擦学性能。.利用二氧化硅颗粒考察了粒径对菜籽油摩擦学性能的影响，在不同润滑区间，粒径对摩擦学性能的影响不同：在边界润滑区，粒径越小的二氧化硅越容易进入摩擦副表面形成摩擦膜的能力越强，抗磨效果越好；在弹流区粒径越大的二氧化硅的减摩性能越好。不同官能团修饰的二氧化硅的摩擦学性能与其在金属表面的吸附性能相关，粒径基本相同的表面含甲基、乙烯基和环氧基团的二氧化硅纳米微粒的在金属表面的平衡吸附质量的不同造成其在摩擦过程生成的吸附膜的厚度和牢固程度的不同，进一步影响了摩擦学性能。.本项目发表论文20篇，其中SCI和EI收录论文18篇；参与撰写学术专著1部；授权国家发明专利8件；获得河南省科学技术奖一等奖1项；培养博士生3名，硕士生9名。