过热对铁液质量和激冷铸铁凸轮轴组织的影响

Effect of Superheat on the Quality of Melt Iron and Microstructure of Chilled Iron Camshaft

研究了1t中频炉铁液过热对铁液质量和激冷铸铁凸轮轴组织的影响。结果表明:随着过热时间的延长,化学成分中碳的烧损严重,其余元素变化不大,铁液白口倾向加大;铸件D、E型石墨数量增多,基体碳化物含量增多。在实际生产过程中,适宜的过热温度为1550℃以下,过热时间应控制在1h内,超过1h需采用补加生铁或增碳剂来增碳、降低白口倾向。

The effect of superheat on characteristics of melt iron and microstructure of chilled iron camshaft was studied in a 1 t intermediate frequency induction furnace. The results show that with the prolongation of superheating time, the reduction of carbon content of melt iron is considerable, while the changes of the other elements are negligible, and the chill tendency of melt iron increases remarkably; the mounts of D-style graphite and E-style graphite in the castings increase significantly, and the mounts of carbide in camshaft castings also increase. The results indicate that the reasonable superheating temperature should be under 1 550℃ and superheating time should be controlled in 1 hr in the production, If the superheating time is more than 1 h it is necessary to reduce chill tendency by adding pig iron or carburizing agent.