Migration of δ/γ Interface in Low Carbon Steels during Continuous Cooling  

作　　者：Qing-chun LI Yong-feng QI Shu XU Chao WANG Guo-wei CHANG 

机构地区：[1]School of Materials Science and Engineering,Liaoning University of Technology

出　　处：《Journal of Iron and Steel Research International》2014年第9期855-861,共7页

基　　金：Item Sponsored by National Natural Science Foundation of China(51204092);Open Project of Shanghai Key Laboratory of Modern Metallurgy and Materials Processing of China(SELF-2012-02)

摘　　要：The δ-ferrite to γ-austenite phase transformation process of low carbon steel was observed in-situ under a confocal scanning laser microscope and the influence of manganese and chromium on the migration of δ/γ interphase boundary during theδ to γphase transformation was studied. It was found that the δ/γ interphase boundary becomes unstable with the decrease of temperature, from planar to curved morphology during theδ to γ phase transformation of Fe-0.08C steel and Fe-0.08C-0.8Mn steel. But in Fe-0.08C-0.8Cr steel, the δ/γ interphase boundaries are stable with planar morphology during the whole δ-ferrite to γ-austenite transformation. The destabilization of δ/γ inter- phase boundary in Fe-0.08C and Fe-0.08C-0.8Mn steels results from high degree of supercooling and sub-boundaries in 7, respectively. The stabilization of δ/γ interphase boundary in Fe-0.08C-0.8Cr steel results from the slow diffu- sion rate of carbon atom induced by the addition of chromium.The δ-ferrite to γ-austenite phase transformation process of low carbon steel was observed in-situ under a confocal scanning laser microscope and the influence of manganese and chromium on the migration of δ/γ interphase boundary during theδ to γphase transformation was studied. It was found that the δ/γ interphase boundary becomes unstable with the decrease of temperature, from planar to curved morphology during theδ to γ phase transformation of Fe-0.08C steel and Fe-0.08C-0.8Mn steel. But in Fe-0.08C-0.8Cr steel, the δ/γ interphase boundaries are stable with planar morphology during the whole δ-ferrite to γ-austenite transformation. The destabilization of δ/γ inter- phase boundary in Fe-0.08C and Fe-0.08C-0.8Mn steels results from high degree of supercooling and sub-boundaries in 7, respectively. The stabilization of δ/γ interphase boundary in Fe-0.08C-0.8Cr steel results from the slow diffu- sion rate of carbon atom induced by the addition of chromium.

关 键 词：phase transition δ/γ interphase boundary MIGRATION low carbon steel 

分 类 号：TG142.31[一般工业技术—材料科学与工程]