球墨铸铁金相组织缺陷原因及防止方法概述

摘要

比较了球墨铸铁与灰铸铁、碳钢的优缺点,介绍了显微缩松、夹渣、石墨漂浮、开花石墨、球化不良、球化衰退、白口与反白口、片状石墨、碎块状石墨、磷共晶等球墨铸铁金相组织缺陷的特征,分析了化学成分、浇注温度、铸造工艺设计、砂型紧实度、组织遗传、铸件壁厚的大小等因素对这些缺陷形成的影响,并提出了相应的防止措施.最后指出,球墨铸铁的金相组织决定了铸件的性能,根据各种金相组织缺陷形成的原因采取相应的措施,可以提高铸件质量,增强企业的市场竞争力和经济效益.%The advantages and disadvantages of nodular iron and gray cast iron and carbon steel were compared.The microfabrication defects such as micro shrinkage porosity,slag,graphite floatation,exploded graphite,degradated spheroidization,undesirable spheroidization,chilling and anti-chilling,flake graphite,fragmented graphite and phosphorous eutectic.The effects of chemical composition,casting temperature,casting process design,sand compactness,tissue heredity and casting thickness on the formation of these defects were analyzed,and the corresponding preventive measures were put forward.Finally,it was pointed out that the microstructure of nodular cast iron determined the performance of castings.According to the causes of defects in various metallographic organizations,the corresponding measures could be taken to improve the quality of castings and enhance the market competitiveness and economic benefits of company.