A review of solid lubrication based on polyurethane composites

Solid lubricant materials could be used in various extreme conditions owing to the excellent anti-friction and -wear with the low friction coefficient and wear rate. Polyurethane (PU)-based solid lubricants as one of the widely utilized composite materials had been well-known by researchers all over the world. PU-based composite lubricants were commonly segmented into single-phase lubricants and multi-phase lubricants via inorganic or organic lubricant additives. What is more, the modified PU by solid lubricants would endow higher tribological performances than that of single-phase PU-based lubricants. Based on the multi-component synergy, the multi-phase lubricants could significantly improve the PU matrix's lubrication and wear resistance and enhance the comprehensive performance such as corrosion resistance. This paper mainly discussed and summarized the recent development in tribological performances of PU-based composite lubricants, and explored their prospective research directions.