Experimental study on the suspension stability and tribological properties of nano-copper in LCKD-320# lubricating oil

Abstract

Nano-copper has proven that it has an excellent contribution to the friction-reduction, anti-wear and extreme pressure properties of lubricant, as the lubricating oil additive. However, there are few studies on the application of nano-copper in full formulated lubricating oils. The suspension stability and tribological properties of LCKD-320# lubricating oil with nano-copper of varying concentrations were investigated. The results demonstrated that the nano-copper was synthesized via the liquid-phase reduction method with the average particle size of 128 nm. The additions of Tween80 and Span80 were 2 wt% of nano-copper, respectively, which can maintain a most suitable dispersity and stability. When the addition of nano-copper was 0.3 wt%, the friction coefficient under the load of 20 N and the wear scar area (S) were decreased by 25% and 54.4%, respectively, and the maximum non-seizure loads (PB) was increased by 33% as compared with original LCKD-320# lubricating oil. Testing results showed that the LCKD-320# lubricating oil with or without nano-copper both were conformed to the national lubricant standards. The present work will extend the application of nano-copper additive and introduce a new approach to lubricity for the coal mine machinery in future technological areas.