Ingredients and services for the formulation
of lubricants and industrial fluids
Protection of the metal surface against mechanical
damage due to a lubricant film breakdown is a very important
theme when talking about lubricants. The key parameter of a
lubricant regarding wear inhibition is its viscosity.
However, if the system runs under mixed lubrication conditions then the oil film still exists but asperities on the metal surfaces touch each other. Antiwear additives avoid welding of these contacts.
Antiwear additives form a protective film by physical adsorption or chemisorption.
Under very high load conditions (in large gears for example) the oil film can break down. In such regions the two moving metal surfaces may locally weld together, and as the damage progresses the moving parts become one fused together.
Extreme-Pressure additives (often called EP additives) prevent local welding in cases where high load leads to metal - metal contacts.
EP additives mechanism is most often a chemical reaction between the additive and the metal surface.
Lumar antiwear and EP additives include: