Antiwear agent

An antiwear agent, also known as a lubricant additive or wear inhibitor, is a substance added to a lubricating oil to improve its lubricating properties and reduce wear in machinery. The most common antiwear agents are organic compounds known as ZDDP, which are often added to engine oils to reduce friction and wear in engines. These compounds form a protective layer on metal surfaces, reducing metal-to-metal contact and minimizing the rate of wear. Other common antiwear agents include phosphates, sulfur-based compounds, nitrites and esters.