Piston ring and manufacturing method therefor
A piston ring having a hard carbon film formed on at least an external peripheral sliding surface of a piston ring base material, the hard carbon film having an sp2 component ratio within a range of 40% to 80% inclusive as measured by a TEM-EELS spectrum which combines electron energy loss spectrosc...
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Main Authors | , |
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Format | Patent |
Language | English |
Published |
02.10.2018
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Subjects | |
Online Access | Get full text |
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Summary: | A piston ring having a hard carbon film formed on at least an external peripheral sliding surface of a piston ring base material, the hard carbon film having an sp2 component ratio within a range of 40% to 80% inclusive as measured by a TEM-EELS spectrum which combines electron energy loss spectroscopy (EELS) with a transmission electron microscope (TEM), a hydrogen content being in a range of 0.1 at. % to 5 at. % inclusive, and an amount of macroparticles appearing on the surface being within a range of 0.1% to 10% inclusive by area ratio. The hard carbon film is formed on a hard carbon foundation film formed under low-speed film-forming conditions on the side of the piston ring base material, and the hard carbon foundation film is formed with an arc current value 80% or less of the arc current value during the formation of the hard carbon film. |
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Bibliography: | Application Number: US201515104660 |