阳极化高硅铝合金表面膜孔内类水滑石的原位生长与析出铺展行为研究

活塞是舰船、车辆等发动机的核心部件，其材料及表面强化处理方法直接影响着发动机的性能和可靠性。高硅铝合金是高负荷发动机活塞的首选材料，阳极氧化是典型的活塞表面强化处理方法。但由于硅的影响，高硅铝合金阳极氧化膜缺陷多及摩擦学性能不理想等问题，目前尚无一致认可的解决方法。本项目首先针对高硅铝合金阳极氧化膜缺陷多、微结构不连续的问题，采用在电解液中添加表面活性剂的方法，消除硅对氧化膜生成的阻碍作用，得到致密、耐磨的氧化膜，然后在氧化膜孔内原位生长摩擦学功能类水滑石。通过对膜孔中类水滑石生长动力学、复合膜层表界面力学状态、类水滑石析出铺展特性的分析，阐明类水滑石微观结构与其宏观摩擦学性能之间的关联机制，明晰复合膜层的减摩承载机理。本项目的研究成果将为高硅铝合金表面耐磨减摩复合膜层的制备提供相应的理论和技术基础，为突破高硅铝合金活塞极端工况下的应用瓶颈提供摩擦学基础与技术支撑。

Pistons are the core components of engines such as ships and vehicles. Their materials and surface strengthening treatment methods directly affect the performance and reliability of engines. High-silicon aluminum alloy is the preferred material for high-load engine pistons, and anodizing is a typical method of piston surface strengthening treatment. However, due to the influence of silicon, there are many defects in the anodized film of high-silicon aluminum alloy and its tribological properties are unsatisfactory. At present, there is no consensus solution. This project first addresses the problems of high-silicon aluminum alloy anodic oxide films with many defects and discontinuous microstructures by adding surfactants to the electrolyte to eliminate the hindrance of silicon on the formation of oxide films and obtain dense, wear-resistant oxidation membrane. Then the tribological functional hydrotalcite-like compounds is going to grow in-situ in the pores of the obtained anodic oxide. By analyzing the growth kinetics of hydrotalcite-like compounds in the membrane pores, the surface/interface mechanical state of the composite layer, as well as the precipitation and spreading characteristics of the hydrotalcite-like compounds, the following problems will be studied: the correlation mechanism between the microstructure of the hydrotalcite-like film and its macroscopic tribological properties; the mechanism of anti-friction and load-bearing of this composite membrane. The results of this project will provide a corresponding theoretical and technical basis for the preparation of the antifriction and antiwear composite membrane on the surface of high-silicon aluminum alloy. They also could provide tribological basis and technical support for breaking through the application bottleneck of high-silicon aluminum alloy piston under extreme working conditions.