Mechanisms of Swelling of Iron Ore Oxidized Pellets in High Reduction Potential Atmosphere  

作　　者：Run-sheng XU Jian-liang ZHANG Hai-bin ZUO Ke-xin JIAO Zheng-wen HU Xiang-dong XING 

机构地区：[1]School of Metallurgical and Ecological Engineering,University of Science and Technology Beijing [2]State Key Laboratory of Advanced Metallurgy,University of Science and Technology Beijing

出　　处：《Journal of Iron and Steel Research International》2015年第1期1-8,共8页

基　　金：Sponsored by National Natural Science Foundation of China(51104014);National Natural Science Foundation of China and Baosteel(51134008);National Basic Research Program(973Program)of China(2012CB720401)

摘　　要：The influences of the time, temperature and atmosphere on the reduction swelling of oxidized pellets were investigated by single factor experiments. The mechanisms of reduction swelling of oxidized pellets were analyzed and investigated by SEM （scanning electron microscopy） and XRD （X-ray diffractometer） analysis. The results show that the change rules of reduction swelling index of oxidized pellets in different reduction atmospheres are very similar. With the increase of reduction time, the reduction swelling index moves up firstly and then down. When the reduction temperature is above 900 ℃, α-quartz turns into α-tridymite, and the transition generates additional volume expansion effect. The reduction swelling index changes faster in H2 atmosphere than in CO atmosphere. Increasing Ha content in the reduction atmosphere is useful to decrease the reduction swelling index, but it is also easy to cause oxidized pellets cracking.The influences of the time, temperature and atmosphere on the reduction swelling of oxidized pellets were investigated by single factor experiments. The mechanisms of reduction swelling of oxidized pellets were analyzed and investigated by SEM （scanning electron microscopy） and XRD （X-ray diffractometer） analysis. The results show that the change rules of reduction swelling index of oxidized pellets in different reduction atmospheres are very similar. With the increase of reduction time, the reduction swelling index moves up firstly and then down. When the reduction temperature is above 900 ℃, α-quartz turns into α-tridymite, and the transition generates additional volume expansion effect. The reduction swelling index changes faster in H2 atmosphere than in CO atmosphere. Increasing Ha content in the reduction atmosphere is useful to decrease the reduction swelling index, but it is also easy to cause oxidized pellets cracking.

关 键 词：high reduction potential atmosphere oxidized pellet reduction swelling mechanism CRACKING 

分 类 号：TF046.6[冶金工程—冶金物理化学]