球墨铸铁碎块状石墨形成及改善措施

Analysis on Formation of Chunk Graphite in Nodular Iron and Its Improvement measures

介绍了球墨铸铁碎块状石墨的出现严重影响铸件的力学性能,碎块状石墨的形态和形成原因。通过采取快速冷却、降低球化后残余稀土含量、使用含锑或含铋孕育剂、控制高纯炉料的加入量和铁液成分的措施,可有效防止碎块状石墨的产生,保证球墨铸铁件的石墨形态。

The appearance of chunk graphite in nodular cast iron seriously affects the mechanical properties of the casting,the morphology of chunk graphite and the reasons for its formation.By adopting the measures of rapid cooling,reducing the residual rare earth content after spheroidization,using antimony or bismuth instillation agent,controlling the addition amount of high purity charge and the composition of molten iron,the formation of chunk graphite can be effectively prevented and the graphite morphology of nodular cast iron can be guaranteed.