重载下蓖麻油润滑失效规律、机理与控制研究

The high-pressure and heavy-load are unavoidable harsh operations in the development of the aviation, Heavy-duty machinery, advanced manufacturing equipments, etc. The extreme heavy-load operation would result in dramatically shortening the lubrication service life and lubrication failure. The poor biological degradation of the mineral oil-based lubricants exerted larger effects of the pollution on the environment. Based on these above problems, the new idea was proposed that the modified castor oil was to replace the heavy-load gear oil prepared by the mineral-based oils. The variation in lubrication properties and friction pair surfaces were investigated by the friction materials, and the reliable testing methods about lubricant properties were put forward under heavy-load condition. The variation in lubrication properties of the castor oil and friction pair surface were investigated by heavy-load operation, the technique of the heterogeneous molecular were explored about separation, extraction and characterization, and the failure mechanism about the castor oil lubrication was revealed under heavy-load condition. The mechanisms on the castor oil were investigated by the types and ratios of environmental friendly type additives, and control technology of the castor oil as heavy-load lubricants would be proposed. The film-formation properties of castor oil before and after the modification were investigated, the formation reason of the thickness plateau zone was discussed, and the lubrication mechanism of the coupling effect of the frictional pair surface, castor oil and the additives would be established under heavy-load condition. These prospective results of this project would process important theoretical and engineering significance on improving the lubrication properties and service life of the lubricants, keeping the system stable and reliable, and developing green energies.

针对高压重载是航空、重工、先进制造装备等领域发展过程中无法避免的苛刻工况条件，极端的重载工况将导致润滑剂的寿命急剧缩短并产生润滑失效，而生物降解性能差的矿物油基润滑剂对环境产生污染等问题，本项目提出改性蓖麻油取代矿物油基重载齿轮油的新方法。研究重载下摩擦副材料对重载齿轮油的润滑性能和摩擦副表面的影响规律，提出重载下润滑可靠性的测试方法；研究重载对蓖麻油的润滑性能和摩擦副表面的影响规律，探索蓖麻油异构分子的分离、提取和表征方法，揭示重载下蓖麻油润滑失效规律；研究环境友好型添加剂的类型和配比对蓖麻油的作用机理，提出重载下蓖麻油润滑性能的控制方法；研究改性前后蓖麻油的成膜特性，探讨重载下膜厚平台区的形成条件，揭示摩擦副表面、蓖麻油及添加剂之间耦合作用的润滑机理。项目的研究成果将对提高重载下润滑剂的润滑性能与使用寿命、保障系统稳定性与可靠性和发展绿色能源具有重要的理论意义和应用价值。

针对高压重载是航空、重工、先进制造装备等领域发展过程中无法避免的苛刻工况条件，极端的重载工况将导致润滑剂的寿命急剧缩短并产生润滑失效，而生物降解性能差的矿物油润滑剂对环境产生污染等问题，本项目提出改性蓖麻油取代矿物油基重载齿轮油的新方法。通过成品齿轮油的润滑性能研究，提出重载工况下润滑材料性能的测试压力为2.7GPa；通过对负荷(196~1569N)、转速(500~1450r/min)和温度(20~100oC)进行正交试验，研究齿轮油和蓖麻油润滑性能的影响因素，发现负荷、转速和温度对齿轮油和蓖麻油的钢球磨斑直径(简称WSD)方差平方和分别为(4.205、0.218和0.117)和(2.2、1.159和1.034)，表明负荷、转速和温度对两种润滑材料的润滑性能影响依次减小，与齿轮油相比，蓖麻油润滑性能受转速和温度的影响更为显著。通过甲脂化和气质联用仪等获取蓖麻油的分离、提取和表征方法，经过981N、600r/min和60min工况下磨损试验后，发现蓖麻油酸含量从89.25%降低到85.51%，而油酸、亚油酸、棕榈酸、硬脂酸等未发生显著变化，表明蓖麻油酸含量可能成为评价润滑性能失效的指标之一。选用液晶材料4-正戊基-4’氰基联苯5CB、1-己基-3-甲基咪唑四氟硼酸盐离子液体[HMIM]BF4、含氮硼酸酯、新型不含硫磷三嗪衍生物等环境友好型润滑材料为添加剂，在四球试验机上研究添加剂质量分数对蓖麻油润滑性能的影响，提出重载下蓖麻油润滑性能控制方法；建立BP神经网络模型，预测组合添加剂的最佳质量比。当离子液体[HMIM]BF4、含氮硼酸酯、新型不含硫磷三嗪衍生物的质量分数分别为1wt%、0.5wt%、1wt%时，其对应钢球WSD为0.552mm，比纯蓖麻油的WSD降低31.9%；采用钢球vs45#钢盘和钢球vs蓝宝石盘的盘球摩擦副研究重载下改性蓖麻油摩擦学性能，揭示摩擦副表面、蓖麻油及添加剂之间耦合作用机理。项目研究成果将对提高重载下润滑剂的润滑性能与使用寿命、保障系统稳定性与可靠性和发展绿色能源具有重要的理论意义和应用价值。