Research on Tribological Characteristics and Worn Surface Self-Repairing Performance of Nano Attapulgite Powders Used in Lubricant Oil as Addictive

As a kind of natural nanometer materials,the attapulgite has been widely used in industry,agriculture,environment,food substance,medicament and many other fields.Few researches about attapulgite used in lubricant oil as additive were made,and those were only at a preliminary stage of exploration.The tribological characteristics of attapulgite powders with the different contents added to CD 15W/40 lubricant oil were researched through"plane-on-plane"configuration friction and wear tester,and the self-repairing performance of 45#steel worn surface was examined via ring-on-block configuration test.XRD,SEM,EDS,TEM were employed to analyze the surface morphologies and elementary composition of the samples'worn surface.Furthermore,wear self-repairing mechanism of attapulgite additive to lubricant oil was explored.The results showed that:the optimal content of attapulgite powders in oil CD 15W/40 was 0.5 wt%,and the stable friction coefficient can be reduced to 0.02,then the friction reduction performance can be enhanced by 82.5%;Smooth worn surface were formed of the chemical reaction film containing elements O,Si,Fe;Friction reduction and self-repairing mechanism had a relation with the crystal structure of attapulgite.