铸铁合金的遗传效应及其利用

Effects and Application of Inheritance to Cast Iron

研究了亚共晶、过共晶铸铁合金液在不同热状态下的凝固组织，以及组织对力学性能的影响等。发现，炉料对铸件产生明显的组织遗传效应；随合金液过热温度的升高，铸件中石墨相的数量减少且变细、碳化物增多、组织趋于均匀、合金的硬度提高、冲击韧性下降；随合金液保温时间延长，组织遗传性衰退、石墨相球化、碳化物变细。设计的热速处理新工艺能显著提高合金的力学性能。根据遗传观点，分析了试验结果及其意义，探讨了热速处理的作用机理。

The microstructure solidified under different thermal conditions and its effects on mechanical properties of cast iron have been studied. It is found that the charge has obvious inheritance effects on casting microstructure. The amount and size of graphite phase decrease,the amount of carbide increases,meanwhile,the hardness and impact toughness of the alloys reduce along with the rise in the melt temperature.The microstructure inheritance effect declines,the graphite phase spheroidizes and the carbides become finer a long with the holding time of the melt.The new technique of thermal-rate treatment designed by ourselves can greatly improve the mechanical properties of the alloys. The test results are dis cussed and the mechanism of the thermal-rate treatment technique is analysed from the inheritance viewpoint.