热分析特征值对蠕墨铸铁蠕化率的影响  

Influence of Characteristic Value on Vermicular Rate of Vermicular Iron

作　　者：赵玉厚[1] 杨喜岗 杨忠[1] 杨通[1] 李建平[1] 陶栋[1] 

机构地区：[1]西安工业大学材料与化工学院,西安710021

出　　处：《西安工业大学学报》2015年第8期642-647,共6页Journal of Xi’an Technological University

基　　金：陕西省教育厅产业化项目(2012JC13);西安市科技局项目(CXY1342-3)

摘　　要：为了确定炉前铸铁类型和蠕墨铸铁蠕化率,使用数据采集仪记录蠕墨铸铁冷却曲线,并获取冷却曲线的特征值,利用特征值和线性回归法对不同蠕墨铸铁蠕化率进行研究.研究结果表明:当CE和Si/C相同时,铸铁类型与初晶温度TAL、共晶最低温度TEU和再辉温度ΔTr密切相关,再辉温度ΔTr小于5℃时为球墨铸铁,再辉温度ΔTr大于5℃时为蠕墨铸铁.灰铸铁的初晶温度TAL较蠕墨铸铁和球墨铸铁TAL高20℃以上,或灰铸铁的初晶温度(TAL不明显时,共晶最低温度TEU较蠕墨铸铁和球墨铸铁的高10℃以上.蠕墨铸铁的蠕化率与共晶最低温度和再辉温度之间有密切关系,试样的蠕化率可由特征温度值组合表达,其误差在10%以内.In order to determine the type of cast iron and vermicularity of compacted graphite iron inside the furnace,characteristic temperature points of the cooling curves and linear regression are used to analyze different samples.The results show：Relationship between the type of cast iron and characteristic temperature points such as the temperature liquidus temperature（T AL ）,temperature of eutectic（T EU ）and degree of eutectic recalescence （ΔT r ）is clear,while the CE and Si/C are equal.When the degree of eutectic recalescence is less than 5 ℃,ductile iron is produced.When the degree of eutectic recalescence is more than 5 ℃,vermicular iron is produced.Compared with vermicular iron and ductile iron,the temperature liquidus temperature of gray iron is more than 20 ℃.When the temperature liquidus temperature of gray iron is not obvious,the temperature of eutectic of gray iron is more than 10 ℃. Relationship between the vermicular rate and characteristic temperature points such as the temperature of eutectic （T EU ）and degree of eutectic recalescence （ΔT r ）is discovered,the vermicular rate can be expressed by the combination of characteristic temperature,and the error was less than 10%.

关 键 词：冷却曲线 蠕墨铸铁 特征温度 蠕化率 

分 类 号：TG250[金属学及工艺—铸造]