Z.Q. Sun
金属学报(英文版)
The microstructure evolution during deformation enhanced transformation of undercooled austenite of a plain low carbon steel has been investigated by means of hot compression simulation experiment under various conditions of strain rate, deformation temperature and strain. The effect of austenite grain size on the strain enhanced ferrite transformation has been studied. The ferrite dynamic recrystallization involved in successive hot deformation has been explored.
关键词:
deformation enhanced transformation
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齐俊杰
,
杨王玥
,
孙祖庆
,
章晓中
,
董志锋
金属学报
采用Gleeble l500热模拟机进行压缩实验, 研究了Q235级别低碳钢SS400在
750和780 ℃形变强化相变组织演变及动力学的定量特征. 过冷奥氏体形变过程的形变强化相变
按照其转变动力学的特征可分为3个阶段: 前2个阶段的转变动力学方程形式与
J-M-A方程的形式相符, 而第3阶段的转变动力学与J-M-A方程的形式不相吻合.
第1阶段符合Cahn的“位置饱和”机制, 动力学参数n值为4, 对应于铁素体在原奥氏体
晶界及三叉界的形核及快速长大. 第2阶段不符合Cahn的“位置饱和”机制,
n值在1.0-1.5之间, 对应于晶内奥氏体/铁素体前沿畸变区的大量形核.
第3阶段对应于剩余少量形核位置时的转变变缓过程. 变形提高了晶粒的形核
率, 同时促进了晶粒的长大速率; 形变强化相变铁素体晶粒转变初期的长大速
率随应变速率的增加而增大.
关键词:
低碳钢
,
deformation enhanced transformation
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kinetics