Q355B中宽带冷弯开裂原因分析及改进措施  

Analysis and Improvement Approach of Cracking and Cold Bending of Q355B Medium-wide Strip

作　　者：吴航兵 韩益民 王文锋 赵亮 肖国昆 朱羽 WU Hang-bing;HAN Yi-ming;WANG Wen-feng;ZHAO Liang;XIAO Guo-kun;ZHU Yu(Department of Science and Innovation,Kunming Steel&Iron Co.,Ltd.,China Baowu Steel Group Co.,Ltd.,Anning,Yunnan 650302,China;Kunming Steel and Iron Manufacturing Center,China Baowu Steel Group Co.,Ltd.,Anning,Yunnan 650302,China)

机构地区：[1]宝武集团昆钢科技创新部,云南安宁650302 [2]宝武集团昆钢制造中心,云南安宁650302

出　　处：《云南冶金》2021年第6期104-109,共6页Yunnan Metallurgy

摘　　要：采用金相显微镜、扫描电镜等对某钢厂Q355B中宽带冷弯开裂试样进行了原因分析,结果表明:严重的带状组织和大量硫化物夹杂两种不利因素交织是本次Q355B中宽带出现冷弯裂纹的主要原因。根据结果对炼钢工序加强钢液脱硫、脱磷操作,降低钢水中硫、磷含量;延长钢水中夹杂物上浮时间,提升钢水的纯净度;轧制过程中适当提高冷却速度抑制带状组织的形成。经过上述改进措施,Q355B中宽带基本未再出现冷弯开裂,取得了较好的效果。The cracking and cold bending sample of Q355B medium-wide strip of one steel plant was analyzed by metallography microscope,scanning electron microscope and so on,the results show that the main reasons of cracking and cold bending of Q355B medium-wide strip were two negative factors intertweined that serious strip structure and a lot of amount sulphide.According to the above mentioned results,desulphurization and dephosphorization of molten steel in steelmaking process was strengthened,and sulphur and phosphorus content was reduced in molten steel;the floating time of impurities in molten steel was prolonged,the purity of molten steel was improved;the cooling speed can be increased suitably in rolling process can restrain the formation of strip structure.Basically,cracking and cold bending of Q355B medium-wide strip does not reappeared through the above mentioned improvement approach,the results were good.

关 键 词：Q355B中宽带 冷弯开裂 带状组织 硫化物夹杂 改进措施 

分 类 号：TG335.5[金属学及工艺—金属压力加工]