Brasenia Schreberi mucilage as a green lubricant additive exhibiting good tribological properties for steel/steel and steel/aluminium friction pairs

It is still necessary to continue exploring green lubricant additive. This study collected a kind of mucilage from the Brasenia Schreberi (BS) leaves which was an aquatic plant. The BS mucilage was dispersed in synthetic ester (SE) and then employed as a green lubricant under the friction pairs composed of steel/steel and steel/aluminium. The tribological tests of the lubricants were carried out under different friction pairs in details and scanning electron microscopy (SEM) and X-ray photoelectron spectroscopy (XPS) were utilized to characterize the worn out surfaces to understand the lubrication mechanisms. The experimental results suggested that as compared with stearic acid (SA) and Ag, BS mucilage in SE could dramatically improve the friction reducing and anti-wear of SE for both steel/steel and steel/aluminium friction pairs. Based on the SEM and XPS analysis of the worn out surfaces, it suggests that the preferable tribological properties of BS mucilage was mainly related to the effective lubricating films including physical adsorption and tribochemcial lubricating films in the process of the friction.