普碳钢弯折开裂特征及成因分析  

Characteristics and Cause Analysis of Bending Cracking of Common Carbon Steel

作　　者：李秋平 朱立光 孙荣志 张庆军 LI Qiuping;ZHU Liguang;SUN Rongzhi;ZHANG Qingjun(Hebei High Quality Steel Continuous Casting Engineering Technology Research Center,College of Metallurgy and Energy,North China University of Science and Technology,Tangshan 063210,China;College of Material,Hebei University of Science and Technology,Shijiazhuang 050000,China;Tangshan Donghua Iron and Steel Enterprise Group Co.,Ltd.,Tangshan 063303,China)

机构地区：[1]华北理工大学冶金与能源学院河北省高品质钢连铸工程技术研究中心,河北唐山063210 [2]河北科技大学材料学院,河北石家庄050000 [3]唐山东华钢铁企业集团有限公司,河北唐山063303

出　　处：《热加工工艺》2022年第11期159-162,共4页Hot Working Technology

基　　金：国家自然科学基金资助项目(51874137);河北省自然科学基金资助项目(E2020209044)。

摘　　要：利用金相显微镜、体视显微镜和带有能谱分析仪的扫描电镜,对普碳钢材的三种不同弯折后产生的开裂缺陷进行了综合分析。结果表明,冷弯90°方管开裂的主要原因是连铸生产过程中发生保护渣卷渣,随后被轧制到板材皮下,造成基体的不连续所致;消防栓用钢在弯折180°后焊接,在加工过程中焊接处出现开裂,其原因主要是焊接部位温度过高、晶粒异常粗大和在冷却过程中产生网状三次渗碳体,使板材塑性和韧性下降所致;冷弯180°热轧板产生开裂是由于铝硅酸盐夹杂的存在。By using a metallurgical microscope, a stereo microscope and a scanning electron microscope with an energy spectrum analyzer, the cracking defects of three kinds of common carbon steel after bending were analyzed synthetically.The results show that the main reason for cracking of the square tube in 90° cold bending is that the slag coiling occurs during the continuous casting process, it is then rolled under the skin of the plate, resulting in the discontinuity of the matrix.During welding of fire hydrant steel after 180° bending, cracking occurs. The main reason is that the temperature of the welding site is too high, the grain size is unusually large, and the reticular cubic cementite forms during cooling, which reduces the plasticity and toughness of the plate. Cracking of hot rolled plate in 180° cold bending is caused by the presence of aluminosilicate inclusion.

关 键 词：弯折开裂 卷渣 网状渗碳体 铝硅酸盐夹杂物 

分 类 号：TG316[金属学及工艺—金属压力加工] V92[航空宇航科学技术]