Lubrication and corrosion inhibition mechanisms of Rauiella Fujisana extracts as lipid soluble additives

In order to replace the use of inorganic corrosion inhibitors and traditional lubricants, which are known to be harmful to the human body and the environment and are commonly used in industrial applications, the new green additives, which offer an environmentally friendly alternative, show great potential for application. As a green and environmentally friendly plant extract, the Rauiella fujisana (Paris) Reimers extract (RFE) has been demonstrated to possess both antiwear extreme pressure and corrosion inhibition properties for metals.In this study, a substantial number of active ingredients were identified in RFE through the utilisation of Fourier transform infrared spectroscopy (FT-IR) and gas chromatography-mass spectrometry detection (GC-MS). The experimental results demonstrate that the polyalphaolefin (PAO) lubricant containing RFE is capable of reducing the coefficient of friction of 20CrMnTi carburized steel by 72.22 % and the wear rate by 73.77 % at a load of 10 N. The results of experiments conducted using scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS) and four-ball friction test indicate that RFE is capable of enhancing the strength of adsorbed films on metal surfaces. The wet heat method and electrochemical testing revealed that RFE, functioning as an anodic corrosion inhibitor, adsorbed on the metal surface to form an adsorption film through van der Waals forces and chemical bonding forces. The corrosion inhibition efficiency of RFE on pure iron in 3.5 % NaCl solution was determined to be 73.43 %.