Improving powertrain efficiency with low-friction wear resistant Diamor® coatings
Friction is a major cause for powertrain inefficiencies reducing vehicle gas mileage and increasing total carbon dioxide emissions. Traditional oil lubrication may prove insufficient under high loads where the lubricious protective film can disappear leading to substantial friction and potentially critical wear. An example is the oscillating motion between piston rings and cylinder liners in combustion engines. Emerging fuel saving technologies such as start-stop automatics may aggravate friction and wear increasing circumstances even more. Low friction and wear resistant coatings aim to lastingly address some of the deficiencies of traditional liquid lubricants. Fraunhofer’s Diamor® coatings offer excellent friction reduction and wear protection for powertrain components that experience highly loaded contact situations. In collaboration with an industrial partner, Fraunhofer engineers performed experiments comparing the performance of actual engines with and without coated components. The engines were first tested as delivered using standard oil lubrication. Then the engines were disassembled and parts relevant to friction reduction were coated with Diamor®. Finally the reassembled engines were tested again under conditions identical to the first test. The results proved reduced friction, which led to more than 3% increase in peak horsepower and more than 2% power increase across the usable speed range of the engine with Diamor® coated parts. These results demonstrate the tremendous potential to conserve fuel and reduce carbon dioxide emissions for Diamor® coated powertrains.