| 摘要 |
A piston ring (100) comprising upper face (110), a lower face (112), an inner perimeter wall (113), and an outer perimeter wall (114) that extends around the piston ring from the upper face to the lower face, where the outer perimeter wall has upper comer (118) region disposed adjacent the upper face, a lower comer (120) region disposed adjacent the lower face, and a band of a nitrided conversion layer (122) extending between the upper comer region and the lower comer region, and where a PVD nitride layer (128) is disposed on the upper comer region and on the lower comer region. |
