稻壳基陶瓷颗粒摩擦学特性与摩擦催化石墨化机制研究

The incineration and storage of rice husk has brought the serious environmental harm and the utilization of rice husk has become a pressing problem to be solved. One of the approaches to utilize the rice husk is the preparation of rice husk ceramic (RHC) particles. But the hygroscopic surface of RHC limits its applications. In order to weaken its hygroscopic property and strengthen the thermal conductivity, the chemical plating method will be used to metalize the RHC surface to prevent H2O from entering RHC particles in the research project. The behaviors of exfoliation, transferring, and repairing friction pair of the metallization RHC particles will be studied during the friction period. At the same time, the possible RHC crystal transformation on the surface of the preferred catalysts will be investigated. The transforming conditions and mechanism from amorphous carbon into graphite-microcrystal will also be researched by a series of systematic tribological tests. To improve the tribological properties of RHC particles, the project will research the surface metallization for weakening the hygroscopic property, the exfoliation and transferring of the metal plating layer for repairing the friction pair, and the crystal transformation from amorphous carbon into graphite-microcrystal on the surface of catalysts. The results will have excellent theoretical or practical significances in areas, such as the carbon materials tribology, the tribological catalysis, and the utilization of rice husk.

稻壳焚烧与储存给环境带来了严重的危害，合理利用稻壳资源是迫切需要解决的问题。稻壳基陶瓷材料的开发是稻壳资源化利用的新途径之一，但稻壳基陶瓷的易吸湿性严重限制了其应用范围。本项目拟通过化学镀法实现稻壳基陶瓷颗粒的表面金属化改性，抑制其吸湿性并增强其导热性，探索表面金属化稻壳基陶瓷颗粒金属镀层的摩擦剥离、转移及对摩擦副的修复行为；再选择合适的摩擦催化剂，研究金属镀层剥离后的稻壳基陶瓷颗粒在催化剂表面的晶型转变行为，探索无定形碳向润滑结构的石墨碳转变的条件及相关机制。本项目从稻壳基陶瓷颗粒表面金属化抑制吸湿性、摩擦剥离金属镀层对摩擦副表面的修复、摩擦催化诱导形成润滑结构的石墨碳这三个方面出发，改善稻壳基陶瓷颗粒的摩擦学性能，在碳材料摩擦磨损机理、摩擦催化机理与稻壳的综合利用等领域具有较好的理论与实际意义。

本课题旨在解决稻壳的焚烧以及乱堆积给环境带来的污染与安全问题。采用高温碳化稻壳粉制备出陶瓷基颗粒以及化学镀法实现其表面金属化（镍和铜颗粒）改性解决材料吸水性问题，从而提高材料性能。采用一系列现代分析技术对陶瓷基颗粒及改性颗粒的形貌、组分和结构进行系统分析，并对两种颗粒材料的干摩擦和油润滑下的摩擦学性能进行了系统的测试，重点研究了表面金属化陶瓷颗粒摩擦磨损机制及摩擦诱导催化生物质碳石墨化机制。.生物质陶瓷颗粒为片层结构，颗粒大小为微米颗粒；主要成分是无定型碳和二氧化硅。化学镀法实现陶瓷颗粒界面纳米镍和铜颗粒的包覆。纯陶瓷颗粒的干摩擦实验表明陶瓷颗粒主要以磨粒磨损为主；陶瓷颗粒与固体润滑剂石墨和二硫化钼具有很好的协同抗磨减摩特性；但复合材料高载荷和转速下，材料磨损率会急剧增加。改性后的陶瓷颗粒可明显的改善铁基和铝基复合材料的摩擦学特性，其摩擦机制低温下以磨粒磨损为主；高温下磨损形式从磨粒磨损向粘滑磨损转变。在摩擦力的作用下，摩擦诱导颗粒界面金属涂层剥离转移到对偶件表面形成转移膜，碳结构发生变化，进而起到抗磨减磨的功效。.陶瓷颗粒可作为润滑油的高温摩擦改进剂，其摩擦磨损机制主要是摩擦诱导陶瓷颗粒组分参与润滑膜的形成。利用生物油燃烧碳微粒替代陶瓷颗粒初步研究了摩擦催化石墨化机制。发现摩擦诱导碳材料参与润滑膜形成，且膜的组分中Csp2和Csp3发生变化，可通过控制摩擦膜中碳组分调控稻壳基陶瓷颗粒的摩擦学行为。.成功制备出了一种新型的生物质基陶瓷颗粒摩擦改进剂，不仅实现了稻壳资源的充分利用降低环境污染问题，而且在摩擦催化理论和拓展碳材料摩擦学原理等领域都具有重要的理论意义和实际的应用价值。