Synthesis and tribological properties of zinc dodecoxyborate as antiwear and friction reducing additive of lubricating oil

Oil-soluble zinc dodecoxyborate was synthesized. Its tribological properties as a lubricating oil additive were evaluated by using four-ball and ring-on-block tribotesters. The results indicate that the wear resistance and load-carrying capacity of 500SN base oil are increased and the friction coefficient is decreased. The wear scar was observed with SEM. It was found that the scuffing of the tested steel ball lubricated with additive-containing base stock is greatly abated as compared with that lubricated with base stock alone. It was suggested that tribochemical reactions are involved in the friction process, which generate a protective film containing boride on the lubricated steel surface. This contributes to improve the antiwear and extreme pressure properties of the base stock.