连续加热球墨铸铁奥氏体化转变动力学  

Austenite transformation kinetics of ductile cast irons during continuous heating

作　　者：魏铁石 王晶[2] 黄宝旭[1] 马杰[1] 赵性川 王长征[1] 

机构地区：[1]聊城大学材料科学与工程学院,山东聊城252000 [2]海军飞行学院,辽宁葫芦岛125001

出　　处：《材料热处理学报》2018年第1期152-158,共7页Transactions of Materials and Heat Treatment

基　　金：山东省自然基金(ZR2012EMM007);山东省科技发展计划项目(2014GGX102016);聊城大学大学生科技文化创新基金(26312171922)

摘　　要：基于差示扫描量热法（DSC）实验数据,采用John-Mehl-Avrami（JMA）方程研究了球墨铸铁非等温奥氏体化动力学。结果表明：球墨铸铁的最佳奥氏体化温度在1173 K左右,奥氏体化过程主要受铁原子的扩散控制;奥氏体固态相变的动力学参数n随加热速率的增加而减小,但生长速率因子系数k0基本上为一常数,约为6.1×10^9。在此基础上研究了球墨铸铁奥氏体等温转变动力学曲线,并且通过金相观察法对奥氏体转变曲线进行了验证,与计算结果符合较好。Non-isothermal austenite transformation kinetics of ductile cast irons （DCIs） was investigated by using John-Mehl-Avrami equation based on differential scanning calorimetry （DSC） experiments data. The results show that the optimal austenitizing temperature of the DCIs is about 1173 K and the austenitizing process is mainly controlled by the diffusion of Fe atoms. In addition, the theoretical analysis also indicates that the kinetic parameters nof solid phase transformation of the austenite decreases with the increasing of the heating rate and the coefficient of growth rate factor （ k0 ） is essentially a constant, about 6.1 × 10^9. Furthermore, the isothermal transformation kinetics curves of the austenite in the ductile iron during heating has been studied, and the austenite transformation curves have been verified by metallographic observation, which is in good agreement with the calculated results.

关 键 词：球墨铸铁 奥氏体化 差示扫描量热法(DSC) 转变动力学 

分 类 号：TG143.5[一般工业技术—材料科学与工程]