灰铸铁件的氮气孔及其防止

Nirogen Blow Hole of Gray Iron Castings and Its Prevention

叙述灰铸铁件裂隙状氮气孔的主要特征、形成机理。铁液含氮量高引起的氮气孔的防止方法是:铁液中加入钛铁,降低铸铁白口倾向和正确选用增碳剂。防止树脂砂含氮量高引起的氮气孔的方法是:选用低氮树脂、型砂或涂料中加入氧化铁粉和避免树脂受潮。

The main features of the fissure type nitrogen blow hole and its formation mechanism was described. The measures to prevent nitrogen blow hole caused by high nitrogen content of molten iron are: adding ferro-titanium into molten iron, reducing chilling tendency of the cast iron and correctly choose recarburizer. The measures to prevent nitrogen blow hole caused by high nitrogen content of resin sand are: adopting low nitrogen resin, adding iron oxide into sand or coating and keeping resin from moisture.