Abstract

Oils and grease have beneficial effects on moving parts such as connecting rod, gears, shafts, and engine to reduce wear and friction. The properties of lubricants such as tribological and rheological properties are an important role in oils and grease characterization. Nano additives on lubricant oils play an important role in anti-wear; reduce the coefficient of friction and enhance the rheological properties. The Tribological and rheological behavior of base oil 15W50 which have different concentrations of multi-wall Carbon Nanotubes (MWCNTs) (0.5, 1, 1.5, and 2 wt%), and constant amount of graphene nanosheets (GNSs) (0.5 wt%) were investigated. This research is the first one in studying the effect of hybrid nano additives of (MWCNTs) and (GNs) on the tribological and rheological properties of lubricant oils. Tribological characterization was carried out on four ball testing model under different loads (200, 400, 600, and 800 N). The kinematic viscosity, flash point, pour point, and thermal conductivity of nanofluid added 15W50 lubricant are estimated and compared with base oil. The results showed that nano additives improve the wear scar and coefficient of friction by 78% and 48%, respectively. The flash point, thermal conductivity, kinematic viscosity, and pour point, were improved by 15%, 77%, 76.8%, and 20%, respectively compared with the base oil. The hybrid addition of CNTs/GNs nanoparticles enhanced the properties of 15W50 engine oil.

摘要

油和油脂对连杆、齿轮、轴和发动机等运动部件具有减少磨损和摩擦的有益作用。润滑剂的特性，例如摩擦学和流变学特性，在油和润滑脂表征中起着重要作用。润滑油中的纳米添加剂在抗磨方面起着重要作用；降低摩擦系数，提高流变性能。具有不同浓度多壁碳纳米管 (MWCNTs) (0.5、1、1.5 和 2 wt%) 和恒定量石墨烯纳米片 (GNSs) (0.5 wt%) 的基础油 15W50 的摩擦学和流变学行为分别为调查。这项研究是第一个研究 (MWCNTs) 和 (GNs) 混合纳米添加剂对润滑油摩擦学和流变学性能影响的研究。在不同负载（200、400、600 和 800 N）下的四球测试模型上进行了摩擦学表征。估算了添加纳米流体的 15W50 润滑剂的运动粘度、闪点、倾点和热导率，并与基础油进行了比较。结果表明，纳米添加剂分别将磨痕和摩擦系数提高了 78% 和 48%。与基础油相比，闪点、热导率、运动粘度和倾点分别提高了15%、77%、76.8%和20%。CNTs/GNs 纳米颗粒的混合添加增强了 15W50 发动机油的性能。估计纳米流体添加15W50润滑油的导热系数，并与基础油进行比较。结果表明，纳米添加剂分别将磨痕和摩擦系数提高了 78% 和 48%。与基础油相比，闪点、热导率、运动粘度和倾点分别提高了15%、77%、76.8%和20%。CNTs/GNs 纳米颗粒的混合添加增强了 15W50 发动机油的性能。估计纳米流体添加15W50润滑油的导热系数，并与基础油进行比较。结果表明，纳米添加剂分别将磨痕和摩擦系数提高了 78% 和 48%。与基础油相比，闪点、热导率、运动粘度和倾点分别提高了15%、77%、76.8%和20%。CNTs/GNs 纳米颗粒的混合添加增强了 15W50 发动机油的性能。