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Laser glazing of steel is being investigated as a means of improving its tribological properties for railroad and other applications. The microstructure of the surface layer on 1080 steel formed by the process was characterized by optical and transmission electron microscopy (TEM) and microhardness measurements. The microhardness increases were consistent with self-quenching of the 1080 steel, followed by tempering of adjacent areas. TEM revealed a very fine (5-10 nm) grain size. Friction and wear tests were conducted on glazed and unglazed materials with a pin-on-disc test rig. Laser glazing reduced both friction and wear during dry tests. The improved friction and wear performance is attributed to the microstructural changes of the near-surface region by laser glazing.

An increase in engine and vehicle efficiency usually requires an increase in the severity of contact at the interfaces of many critical components. Examples of such components include piston rings and cylinder liners in the engine, gears in the transmission and axle, bearings, etc. These components are oil-lubricated and require enhancement of their tribological performance. Argonne National Laboratory (ANL) recently developed a carbon-based coating with very low friction and wear properties. These near-frictionless-carbon (NFC) coatings have potential for application in various engine components for performance enhancement. This paper presents our study of the tribological performance of NFC-coated steel surfaces when lubricated with fully formulated and basestock synthetic oils. The NFC coatings reduced both the friction and wear of lubricated steel surfaces. The effect of the coating was much more pronounced in tests with basestock oil.

The sulfur content in diesel fuel has a significant effect on diesel engine emissions, which are currently subject to environmental regulations. It has been observed that engine particulate and gaseous emissions are directly proportional to fuel sulfur content. With the introduction of low- sulfur fuels, significant reductions in emissions are expected. The process of sulfur reduction in petroleum-based diesel fuels also reduces the lubricity of the fuel, resulting in premature failure of fuel injectors. Thus, another means of preventing injector failures is needed for engines operating with low- sulfur diesel fuels. In this study, we evaluated a near-frictionless carbon (NFC) coating (developed at Argonne National Laboratory) as a possible solution to the problems associated with fuel injector failures in low-lubricity fuels.

In an effort to reduce fuel consumption and emissions, hybrid vehicles incorporating fuel cell systems are being developed by automotive manufacturers, their suppliers, federal agencies (specifically, the U.S. Department of Energy) and national laboratories. The fuel cell system will require an air management subsystem that includes a compressor/expander. Certain components in the compressor will require innovative lubrication technology in order to reduce parasitic energy losses and improve their reliability and durability. One such component is the air bearing for air turbocompressors designed and fabricated by Meruit, Inc. Argonne National Laboratory recently developed a carbon-based coating with low friction and wear attributes; this near-frictionless-carbon (NFC) coating is a potential candidate for use in turbocompressor air bearings. We presents here an evaluation of the Argonne coating for air compressor thrust bearings.