| 摘要 |
PURPOSE:To improve mainly the anti-abrasive property extensively by forming ring grooves made by groove-processing a fused and diffused layer of an aluminum-copper alloy at the peripheral surface of a piston main body which consists of an aluminum alloy, and setting the including amount of the copper within a specific scope. CONSTITUTION:At the upper end of the peripheral surface of a piston main body 1 which consists of an aluminum alloy, the top ring groove 2 and the second ring groove 5 are engraved respectively. In the ring grooves 2 and 5, the top ring 3 and the second ring 4 are geared partially, and the remaining parts projecting from the peripheral surface are slided with the inner surface of a cylinder 6. In this case, the top ring groove 2, for example, is formed by inserting a copper wire material 8 in the engraved groove 7, and after radiating electron beams B to the copper wire material 8, by applying a groove- process to the fused and diffused aluminum-copper alloy layer 9. The copper amount included in the ring groove 2 is set within 10-35wt.%. |
