Antiwear and extreme pressure additives

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:

• - Amine phosphates
• - Complex esters
• - Dithiophosphates
• - Organic friction modifiers
• - Phosphates
• - Phosphites
• - Phosphorothionates
• - Sulfurised esters
• - Sulfurised fatty acids
• - Sulfurised olefins
• - Triarylphosphates

If you require further information such as product technical data sheets and safety data sheets please contact our sales office or send us your request from our contact page.