我厂生产的球铁件主要有两种牌号QT 40-17、QT 42-10生产工序为:冲天炉熔炼→炉前冲入法处理→铸件经900～920℃高温退火。在球铁生产中,锰含量一般限制为<0.5％。但是,实际上,球铁件的含锰量一般是随进货生铁的含锰量多少(一般<0.5％)而有所波动的,而且并不另行调整。我厂在生产上述两种牌号的球铁件时,发现少数楔形试 I produced the ductile iron pieces mainly two brands QT 40-17, QT 42-10 production processes are: cupola furnace → front into the furnace processing → casting by 900 ~ 920 ℃ high temperature annealing. In ductile iron production, the manganese content is generally limited to <0.5%. However, in fact, the amount of manganese contained in ductile iron pieces generally fluctuates with the amount of manganese contained in the incoming pig iron (typically <0.5%) without any further adjustment. I plant in the production of the above two brands of ductile iron pieces, found a few wedge-shaped test