王星全^1,2, 刘 涛^1,2, 王占宜^1,2, 徐 涛^1,2 , 丁文开^1,2

1.滨州渤海活塞有限公司，山东 滨州 256602；

2. 山东省发动机活塞摩擦副重点实验室，山东 滨州 256602

摘要：针对某缸径为135 mm的高强化柴油机铝活塞销孔出现的异常磨损和开裂现象，综合分析活塞尺寸和探伤检测结果及材料检测结果等，结合活塞销孔失效机理，判定显微缩松是导致此次活塞销孔失效的根本原因，并对活塞铸造工艺进行优化改进。对优化后的活塞进行可靠性试验和小批量生产验证，活塞销孔没有出现失效故障，改进方案有效。

关键词：铝活塞；销孔；失效；显微缩松；金相组织

Abstract：In view of the abnormal wear and cracking of the aluminum piston pin hole of a 135mm high strength diesel engine, through the comprehensive analysis including the piston design and test results, the comparison between the failed piston and the normal piston. It is determined that the micro shrinkage is the main cause of the failure of the piston pin hole. Based on this conclusion, the piston casting process was optimized and improved. The optimized piston could pass all the tests of diesel engine.

Key words：aluminum piston; pin hole; failure; micro-shrinkage; microstructure