对准铸态贝氏体铸铁组织的观察和分析

The Observation and Analysis of Quasi as Cast Bainitic Microstructure

深入观察分析了准铸态贝氏体铸铁中贝氏体组织的形成规律及结构特点，发现：在准铸态工艺下，贝氏体组织除能在母相奥氏体界面上形核外，还可在石墨／奥氏体界面上形核；当贝氏体在片状石墨界面形核时，在石墨端部一般形成上贝氏体，侧面形成下贝氏体；准铸态贝氏体铸铁中的贝氏体亦属无碳化物贝氏体。

Abstract A through observation and analysis have been undertaken on the microstructure of quasi as cast bainitic cast iron and the formation regularity and structure features of the bainitic microstracture were also discussed.The results indicated that,under the conditions of quasi as cast technology,the bainite can nuc leate not only on the austenite grain boundaries,but on the interface of graphite/austenite.When nucleated on the interface of flake graphite,upper bainites can be formed at the end of graphite and lower bainites on the both sides of the graphite.The bainites in the microstructure of quasi as cast bainitic cast iron are bainites without carbide.