等温淬火球墨铸铁前轴的生产实践

Production Practice of Austempered Ductile Iron Front Axle

介绍了最大壁厚为110 mm球墨铸铁前轴的铸件结构及生产情况,针对生产中出现的铸件断面石墨球数少以及碎块状石墨,通过增加冷铁强制冷却,球化时添加纯La低RE球化剂,热包时随流加入石墨型增碳剂以及采取包内孕育+型内孕育+随流孕育的3次孕育等措施,使铸件厚大位置的球化率≥85%、石墨球数达到130个/mm^(2),满足使用要求。

The structure and production of the front axle of nodular cast iron with the maximum wall thickness of 110 mm were introduced.In view of the small number of graphite balls in the section of the casting and the broken graphite in the production,the casting was made by adding the forced cooling of cold iron,adding pure La and low RE nodularizing agent during spheroidizing,adding graphite type carburizing agent along with the flow during hot ladle,and adopting three inoculations of in ladle inoculation+current inoculation+in mold inoculation.Finally,the spheroidization rate of thick position is more than 85%,and the number of graphite balls reaches 130 per mm^(2),which meets the requirements of application.