| 摘要 |
The invention relates to a two-part piston (1) for an internal combustion engine, consisting of an upper part (2) and a lower part (3) which is screwed to the upper part. The upper part (2) and the lower part (3) are in contact with each other, partially by means of inner bearing surfaces (25, 26) defining the lower side of an upper ring rib (10) and the upper side of a lower ring rib (11), and partially by means of outer bearing surfaces (28, 29) defining the lower side of the ring wall (9) and the upper side of a collar (27) applied to the lower part (29). In order to avoid frictional rubbing, frictional heat sealing and pressure-related material heat sealing, at least one of the bearing surfaces (25, 26, 28, 29) is easily and economically provided with a chrome layer (30) which has a structured surface comprising a plurality of raised parts and recesses. |
