类水滑石减摩材料制备及其减摩机理研究

发布时间：2018-06-26 05:25

本文选题：类水滑石 + 减摩抗磨　；参考：《中国地质大学(北京)》2015年博士论文

【摘要】：类水滑石作为应用广泛,环境友好的层状矿物,本课题组前期的研究已验证了其优良的减摩抗磨性能。但其作为润滑油减摩抗磨自修复添加材料的研究刚刚起步,目前的研究大多集中在摩擦学性能的简单评价。基于以上原因,本文开展了微-纳米类水滑石的制备、插层改性、热处理和摩擦学性能评价,采用多种表面分析手段对摩擦磨损表面的形貌和化学环境进行了表征,分析了类水滑石与摩擦副表面及复配添加剂的作用过程、减摩抗磨和成膜机理、晶体在摩擦作用下的变化,对类水滑石在摩擦学领域的系统深入研究将为其工业化和产品化提供重要的理论和技术支持。本文制备了Ni-Al、Mg-Al和Co-Al类水滑石及其有机插层改性粉体,得到了优化的制备和改性条件。通过四球摩擦实验机、齿轮摩擦实验机和高频微动摩擦实验机评价了其作为润滑油基础油和商用润滑油添加材料的减摩抗磨性能。采用扫描电子显微镜、原子力显微镜、X射线能谱分析和X射线近边吸收谱分析对摩擦表面进行了表征,结合摩擦学数据得出了类水滑石对润滑油摩擦学性能改善的作用机理。研究结果表明:Ni-Al、Mg-Al和Co-Al类水滑石微-纳米粉体均能有效提高基础油的减摩抗磨性能;Mg-Al类水滑石的热处理能够提高粉体的减摩性能,但在添加量不变的情况,会减弱粉体的抗磨损性能;添加Co-Al类水滑石能使基础油的摩擦系数降低19%-22.3%,摩擦副的磨斑直径减小33%。摩擦表面形貌分析表明,摩擦作用过程中水滑石颗粒可以吸附在摩擦副表面,防止相对运动摩擦表面的直接接触,降低摩擦系数、磨损量、摩损表面粗糙度、磨痕密度和深度。类水滑石的加入还可有效防止基础油的氧化,消除硫酸盐对钢副表面的腐蚀。类水滑石在摩擦作用后结构发生变化,晶体颗粒的有序度降低,Al的部分配位环境由八面体变为四面体,这是降低摩擦系数的因素之一。类水滑石与二烷基二硫代磷酸锌(ZDDP)复配使用时,在成膜过程中两者存在竞争作用,使得ZDDP摩擦膜中形成短链多磷酸盐,同时会使摩擦膜近表面的硫化物氧化,增大了含复配剂样品的摩擦系数。Co-Al类水滑石与ZDDP长时间复配使用时,类水滑石会使摩擦膜内产生Fe S,表明类水滑石的添加可以提高ZDDP的极压性能。
[Abstract]:Hydrotalcite is a widely used and environmentally friendly layered mineral, and its excellent antifriction and antiwear properties have been verified by our previous research. However, the research on the antifriction and antiwear self-repairing additive of lubricating oil is just beginning, and most of the current researches focus on the simple evaluation of tribological properties. For the above reasons, the preparation, intercalation modification, heat treatment and tribological performance evaluation of micro-nano hydrotalcite were carried out. The morphology and chemical environment of friction and wear surfaces were characterized by various surface analysis methods. The process of action of hydrotalcite with the surface of friction pair and the compound additive, the mechanism of antifriction and film formation, and the change of crystal under friction are analyzed. The systematic study of hydrotalcite in tribology will provide important theoretical and technical support for its industrialization and production. Ni-Al Mg-Al and Co-Al hydrotalcite and their organic intercalation modified powders were prepared in this paper. The optimized preparation and modification conditions were obtained. The friction and antiwear properties of four ball friction tester, gear friction tester and high frequency micro dynamic friction tester were evaluated as lubricating base oil and commercial lubricating oil additive materials. The friction surface was characterized by scanning electron microscope (SEM), atomic force microscope (AFM) X-ray spectrum analysis and X-ray near-edge absorption spectrum analysis. Combined with tribological data, the mechanism of improving the tribological properties of lubricating oil by hydrotalcite was obtained. The results show that the friction and antiwear properties of the base oil can be improved effectively by both the micro and nano powders of water talcite such as: Ni-Al Mg-Al and Co-Al hydrotalcite. The heat treatment of Mg-Al hydrotalcite can improve the friction-reducing performance of the powder, but when the amount of the powder is constant, the friction and antiwear properties of the base oil can be improved. Addition of Co-Al hydrotalcite can reduce the friction coefficient of base oil by 19% -22.3and reduce the diameter of wear spot of friction pair by 33%. The surface morphology analysis shows that the water talc particles can be adsorbed on the surface of the friction pair during the friction process to prevent the direct contact of the relative moving friction surface and to reduce the friction coefficient, wear amount, surface roughness, abrasion density and depth. The addition of hydrotalcite can also effectively prevent the oxidation of base oil and eliminate the corrosion of steel secondary surface caused by sulphate. The structure of hydrotalcite changes after friction, and the order degree of crystal particles decreases from octahedron to tetrahedron, which is one of the factors that decrease the friction coefficient. When the hydrotalcite is combined with zinc dialkyldithiophosphate (ZDDP), there is competition between the two in the process of forming the film, which results in the formation of short chain polyphosphate in the ZDDP friction film and the oxidation of sulfide near the surface of the friction film. The friction coefficient of the sample containing the admixture. Co-Al hydrotalcite and ZDDP were increased for a long time, the hydrotalcite-like material produced Fe S in the friction film, which indicated that the addition of hydrotalcite-like material could improve the extreme pressure performance of ZDDP.
【学位授予单位】：中国地质大学(北京)
【学位级别】：博士
【学位授予年份】：2015
【分类号】：TB39

【相似文献】