A new piston ring coating has been developed by the Federal-Mogul Powertrain Segment (federalmogul.com) that is said to have a combination of durability and friction reduction that can result in improved fuel economy in both gasoline and diesel engines.
“DuroGlide,” as the coating is named, is based on an amorphous high-hardness carbon-based coating that (1) improves lubricity between surfaces by providing a physically and chemically inert barrier and (2) contains around 50% diamond-structured carbon.
As a result of this wear resistance and low friction, Federal-Mogul developers have found that depending on the engine application, there can be fuel economy savings up to 1.5%, or a CO2 reduction up to 3 g/km.
“Until now, the high durability carbon-based coatings available on the market have usually been restricted to a maximum of a few microns thickness because greater thicknesses increase residual stresses, leading to a higher risk of delamination,” said Dr. Marcus Kennedy, manager, physical coatings, Rings & Liners, Federal-Mogul Powertrain. Federal-Mogul has developed a surface treatment and physical vapor deposition process that permits a coating thickness of more than 20 microns without the risk of delamination.
The coating is applicable to all “known piston ring materials made of cast iron or steel.”
It will go into production in 2014.