Study on Reaction Mechanism of Sulfur and Phosphorus Type Additives Using an Acoustic Emission Technique

Sulfur and phosphorus additives are used in lubricants as extreme-pressure antiwear agents, which typically together to ensure reliability over a wide range of lubrication conditions. However, the working mechanism combined additive system has not been clearly defined due difficulties obtaining information on material surface where these work. This is because this constantly being worn during testing. Therefore, situ analysis applying an acoustic emission (AE) technique was proposed. AEs elastic stress waves generated deformation fracture solids, can be measured real-time, providing with respect magnitudes types damage. In paper, application AE helps clarify how each acts real-time. The understand improved using both sulfur phosphorous investigated by technique, along conventional methods. It concluded that wear reducing properties were reaction remove protruded parts, followed form protective film.