高速发动机气缸体渗漏缺陷分析及控制

Leakage and Prevention of High-speed Engine Cylinder Body

高速发动机气缸体铸件发生渗漏。为此，采用扫描电镜等仪器对气缸体不同渗漏部位的显微组织和化学成分进行了分析。分析发现，导致高速发动机气缸体渗漏的原因为回水道夹杂物贯通、油道缩松以及部分挺杆砂芯的芯撑未融合。为解决铸件的渗漏问题，进行了模拟试验和工艺优化。试验结果表明，更改内浇道的位置及尺寸、减少芯撑与铁液的接触面积、优化扒渣工艺及提高集渣剂质量等措施，使气缸体铸件渗漏废品率从3．14％降低到了1．30％。

High-speed engine cylinder body exhibited leakage. For this fact, different leakage positions in the cylinder body were subjected to chemical composition analysis and microstructural survey. From the analysis results it was found that the leakage of high-speed engine cylinder body was attributed to penetration flume inclusions, oil duct shrinkage and chaplet not fused. The simulation test and process optimization were performed to remove the casting leakage. The results indicated that percentage of the waste cylinder body castings due to leakage has been reduced from 3.14% to 1.30%.