【摘要】 为提高铸铁气缸套的内在质量,改善其切削性能,降低加工成本,采用5t水冷冲天炉熔炼铁液,电炉保温的双联熔炼工艺,并采用合金光谱快速分析仪对铁液化学成分进行实时监控;利用金相显微镜对气缸套的原辅材料各合金元素对材质的微观组织和宏观特性的影响进行了分析。结果表明:调质过程中加入一定配比的Cr(0.25%)、Mo(0.40%)和Cu(0.3%)等合金元素,促使组织细化,可达到提高增碳率的目的;金属型离心铸造气缸套时铸件质量与水冷时间应相适宜限制了组织中D、E型石墨的形成;含钡孕育剂能够获得分布均匀,形态细长的A型石墨。原辅材料、铸造工艺、合金元素等是造成气缸套加工性能差异很大的主要因素。更多还原

【Abstract】 In order to improve the inner quality of the cast iron cylinder sleeve and its cutting performance, and reduce production cost, the duplex smelting process was adopted, in which the iron is melted in the 5 t water cooling cupola and held in the electric furnace. Real-time chemical composition of iron melt is monitored by optical spectrum analyzers. Effects of alloying element of raw materials on the microstructure and macroscopic characteristics of cylinder sleeve were analyzed using metallographic microscope. The results show that increasing rate of recarburizing and microstructure refinement can be obtained by adding alloying elements in proportion as Cr (0.25%), Mo (0.40%) and Cu (0.3%). In metal mold centrifugal casting, the mass of casting should fit in with water cooling time, so as to restrict the formation of D and E type graphite. Well-distributed and slender A type graphite was obtained by adding inoculant with Ba. The main reasons of the differences in the cylinder sleeve processing performance attribute to the raw and auxiliary materials, casting process and the alloying elements.更多还原