定向凝固条件下亚共晶铸铁凝固特性的研究

Solidification Characteristics of Unidirectionally Solidified Hypoeutectic Cast Iron

用定向凝固方法,对亚共晶成分铸铁的凝固特性进行了研究。结果表明,当铸铁按稳定系凝固咸灰口铁时,先共晶奥氏体枝晶的数量和发达程度随凝固速度的增大面增加。面当铸铁按介稳系凝固成白口铁时,先共晶奥氏体枝晶的数量和发达程度都基本上不随凝固速度的变化面改变。分析指出,灰铸铁的共晶凝固温度随凝固速度的增大面降低,而白口铁很难过冷,其共晶凝固温度基本不变．

Abstract Solidification characteristics of hypoeutectic cast iron were studied with the technique of unidirectional solidifcation. It is found from the experimental results that with the increase of solidification rate, the eutectic temperature of hypoeutectic gray iron decreases, the amount and flourish extent of proeutectic austenite dendrites increase. On the contrary, the eutectic temperature, the amount and flourish extent of proeutectic austenite dendrites are essentially unchanged with the variation of solidification rate in hypoeutectic white iron.