纳米CaB/MoDDP复合润滑油添加剂的摩擦学性能

Tribological performance of nano CaB/MoDDP compound lubricant additive

为提高润滑油的抗磨减摩性能,提升机械设备在恶劣工况下运行的稳定性和安全性,通过四球机和低速重载摩擦磨损试验机研究纳米硼酸钙(CaB)和二烷基二硫代磷酸钼(MoDDP)复合润滑油添加剂的减摩抗磨性能,期望取得较单一添加剂更优异的润滑效果。研究结果显示:制备的纳米CaB为不规则的纳米薄片状,平均尺寸为50~150 nm,经油酸改性后在基础油中具有良好的分散稳定性;纳米CaB和MoDDP均可显著提高润滑油的润滑效果,随着纳米CaB和MoDDP添加质量分数的增加,摩擦因数和磨斑直径呈现先降低后升高的趋势,纳米CaB和MoDDP的最佳添加质量分数分别为2.0%和1.5%;与单一添加CaB、MoDDP相比,复合CaB/MoDDP可进一步改善润滑油的减摩抗磨性能,MoDDP和CaB的最佳质量配比为1.5%∶3.0%,此时摩擦副的摩擦因数最小,磨痕最浅,磨斑直径最小,最大无卡咬负荷最高,并且在低速重载工况下,显示出优良的润滑效果,表明CaB/MoDDP复合润滑油添加剂具有良好的减摩抗磨效果,可以显著提高润滑油的性能。

To improve the tribological properties of lubricant oil and enhance the stability and security of mechanical equipment under severe working conditions,the friction reduction and anti-wear performance of nano-calcium borate(CaB)and molybdenum dialalkyl dithiophosphates(MoDDP)composite additives were studied using four-ball tester and block on ring tester.The results showed that the prepared nano-CaB was a nanosheet with irregular shape and the average size was 50-150 nm.After oleic acid modification,it showed good dispersion stability in base oil.Both nano-CaB and MoDDP could significantly improve the lubrication effect of lubricant oil.With the increasing of nano-CaB and MoDDP mass fraction,the friction coefficient and grinding spot diameter firstly decreased and then increased.The optimal adding mass fraction of nano-CaB and MoDDP was 2.0%and 1.5%,respectively.Compared with single addition of CaB and MoDDP,compound CaB/MoDDP could further improve the friction reducing and anti-wear performance of lubricant oil.The optimal mass fraction ratio of MoDDP and CaB is 1.5%∶3.0%that showed the smallest friction coefficient and grinding spot diameter,and the highest maximum nonseizure load.It also showed excellent lubrication effect under low speed and heavy load condition.