摘要 |
An oil ring for an internal combustion engine is provided that can prevent adhesion and deposition of oil sludge even during long-time operation of the engine, can thereby prevent the occurrence of sticking of the oil ring components to each other, and can maintain a good oil control function. At least part of the surface of the oil ring for an internal combustion engine is coated with a metal coating having a surface free energy of 40 mJ/m2 or less and a hydrogen bonding strength of 1.0 mJ/m2 or less. A coating of Ni, Cu, or an alloy containing Ni or Cu is used as the metal coating. |