液压多路阀蠕铁阀体铸造工艺与微观组织分析

Casting Process and Microstructure Analysis of Vermicular Cast Iron Hydraulic Multi-way Valve

通过分析各种添加元素对蠕墨铸铁的影响，确定了合理的蠕墨铸铁阀体材料蠕化、孕育、熔炼和浇注工艺。利用OM、SEM、EDS分析了蠕墨铸铁的微观组织特征。试验结果表明，石墨蠕化率〉50％，基体组织为铁素体＋珠光体，渗碳体体积〈5％；石墨长宽比为2～10，折叠度为O．7～3，石墨形状系数为0．44~0．57。

Through analyzing the influence of every alloying element on vermicular cast iron, the reasonable processes of vermicularizing, inoculation, melting and pouring for vermicular cast iron valve body were determined. The microstructure characteristic ofvermicular cast iron was analyzed by OM ,SEM ,EDS. The results show that the vermicular rate of graphite is more than 50%, the matrix is ferrite and pearlite, the volume of cementite is lower than 5%. The length to width ratio of the graphite is 2-10. The folding degree of graphite is 0.7-3.0. The shape coefficient of graphite is 0.44-0.57.