铁神一号净化剂对灰铸铁组织和力学性能的影响

Effect of Purifying Agent on the Microstructure and Mechanical Properties of Grey Iron

利用中频感应电炉熔炼灰铸铁铁液,水玻璃砂造型,浇注铸造阶梯试样、φ30mm试棒以及热分析试样,研究了净化剂对其结晶过冷度、组织和力学性能的影响。试验结果表明,单独加入净化剂0.6%可以增加过冷倾向,细化石墨,降低断面敏感性;可以提高灰铸铁的抗拉强度和冶金质量指标;同时加入净化剂0.6%和硅钡孕育剂0.7%对灰铸铁进行复合孕育,明显增加共晶团数量至441个/cm2,可以获得细小A型石墨,显著提高灰铸铁的力学性能σb至282MPa。

The liquid iron was melted in middle frequency induction furnace. The ladder specimed, round specimen of diameter 30 mm and thermal analysis sample was poured in sodium silicate bonded sand mould. The effect of purifying agent on the solidification undercooling, the microstructure and the mechanical properties of gray cast iron specimen was investigated. The results show that the alone additon of purifying agent could increase the undercooling, refine the flake graphite, decrease the sensibility of section and improve the tensile strength and the index of metallurgical quality. In addition, the eutectic cell of grey cast iron can be increased remarkablly by simultaneous addtion of purifying agent and sillican-barium innoculant. The fine and A-type flake graphite can be obtained. The mechanical properties of gray iron could be improved notably.