空间合成碳氢润滑油的真空边界润滑寿命评估

Vacuum Boundary Lubrication Life Assessment of Space Synthetic Hydrocarbon Lubricants

为评估空间润滑油能否满足处于边界润滑工况下的扫描机构8年长寿命要求,分析润滑油在空间环境下的摩擦磨损和长寿命润滑性能。以空间合成碳氢润滑油RP4751为研究对象,分别采用真空螺旋摩擦试验系统(SOT)和滑动摩擦试验系统(SRV)测试润滑油的名义润滑寿命(每消耗1μg润滑油时钢球转动的圈数)、磨斑直径和滑动摩擦因数,结合扫描电子显微镜和X射线能量色散谱仪进行微观分析。结果表明:RP4751润滑油在真空环境下滑动摩擦因数较小、耐磨寿命较长,具有良好的真空边界润滑性能和较高的名义寿命;红外透过率分析结果表明,SRV试验前后润滑油未发生质变。利用2台RP4751润滑油润滑的扫描电机开展1∶1真空寿命试验,结果表明:RP4751润滑油润滑时电机寿命满足红外地球敏感器运动机构的8年在轨运行寿命需求;试验得到的电机轴承中的钢球润滑寿命大于等于2943 r/μg,该结果与SOT试验的润滑油名义寿命3598 r/μg有较好的一致性,为其他空间运动机构润滑油的选用及长寿命润滑设计提供重要试验依据。

In order to evaluate whether the space lubricant can meet long-life requirements of space scanning mechanism under boundary lubrication conditions,the friction and wear and long-life lubrication performance of the lubricating oil in the space environment were analyzed.Taking the space synthetic hydrocarbon lubricant RP4751 as the research object,the vacuum lubrication test system(SOT)and the sliding friction test system(SRV)were used to test the nominal lubrication life(the cycles of steel ball rotation when consuming 1μg lubricating oil),wear spot diameter and sliding friction coefficient of the lubricating oil,and microscopic analysis of the wear spot was carried out by combining scanning electron microscope with an X-ray energy dispersive spectrometer.The results show that the RP4751 lubricating oil has a small sliding friction coefficient and a long wear life in a vacuum environment,and has good vacuum boundary lubrication performance and high nominal life.The infrared transmittance analysis results show that there is no qualitative change of lubricating oil before and after SRV test.The 1∶1 vacuum life test of RP4751 lubricating oil was carried out with two scanning motors.The motor operational life meets the 8-year on-orbit operational life requirements of the infrared earth sensor motion mechanism when lubricated by RP4751 lubricating oil.The lubrication life of steel ball in motor bearing is more than 2943 r/μg,which is in good agreement with the nominal life of lubricating oil 3598 r/μg in SOT test,it provides an important experimental basis for the selection of lubricants for other space motion mechanisms and long-life lubrication design.