Lesson plan
Friction modifier
Friction modifiers are added to lubricants in order to reduce friction and wear in machine components. They are particularly important in the boundary lubrication regime, where they can prevent solid surfaces from coming into direct contact, substantially reducing friction and wear. Several classes of friction modifier additives exist, the main examples being organic friction modifiers (OFMs), oil-soluble organo-molybdenum additives, functionalized polymers, and dispersed nanoparticles. * OFMs are amphiphilic surfactants, such as fatty acids, often derived from fats and vegetable oils. OFMs are important additives in modern engine oils and are also employed in fuels. They adsorb on metal surfaces and self-assemble to form incompressible monolayers which prevent asperity contact and reduce friction and wear. * Organo-molybdenum compounds, were initially developed as antiwear additives but were later recognized to be very effective in reducing boundary friction. They are currently used in many engine oils and, more recently, in gear oils. They reduce friction by forming two-dimensional molybdenum disulphide layers on rubbing surfaces. * Functionalized polymers, which can be tailored to adsorb specifically on polar surfaces, have been shown to markedly reduce friction and wear.…
Article summary
Friction modifiers are added to lubricants in order to reduce friction and wear in machine components. They are particularly important in the boundary lubrication regime, where they can prevent solid surfaces from coming into direct contact, substantially reducing friction and wear. Several classes of friction modifier additives exist, the main examples being organic friction modifiers (OFMs), oil-soluble organo-molybdenum additives, functionalized polymers, and dispersed nanoparticles. * OFMs are amphiphilic surfactants, such as fatty acids, often derived from fats and vegetable oils. OFMs are important additives in modern engine oils and are also employed in fuels. They adsorb on metal surfaces and self-assemble to form incompressible monolayers which prevent asperity contact and reduce friction and wear. * Organo-molybdenum compounds, were initially developed as antiwear additives but were later recognized to be very effective in reducing boundary friction. They are currently used in many engine oils and, more recently, in gear oils. They reduce friction by forming two-dimensional molybdenum disulphide layers on rubbing surfaces. * Functionalized polymers, which can be tailored to adsorb specifically on polar surfaces, have been shown to markedly reduce friction and wear.…
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Discussion questions
- Summarise the article in your own words. Which single claim would you verify first, and why?
- Which claim in this article is most likely to be revised as the sources update? How would you check its current status?
- If two sources disagreed about one of these facts, what would you need in order to trust one over the other?
Bibliography
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Key claims and bibliography are generated from the same tracked claims and sources as the article page.