Analysis of formation mechanism of surface crack of 1215 free-cutting steel during drawing
AI Ke-nan1, ZHANG Pan-pan1, ZHAO Meng-hao1, LI Cheng-liang2, ZHANG Zhi-ming2, FU Jian-xun1
1. Center for Advanced Solidification Technology (CAST), School of Materials Science and Engineering, Shanghai University, Shanghai 200444, China; 2. Manufacturing Department, SGIS Songshan Co., Ltd., Shaoguan 512123, Guangdong, China
Abstract：Surface crack is a common defect of 1215 free cutting steel. In order to explore the cause of surface crack in drawing process of 1215 free cutting steel,the surface crack regions of 1215 free-cutting steel were analyzed and characterized by non-aqueous solution electrolysis,optical microscope and scanning electron microscope. The reason for the surface crack of 1215 free-cutting steel during drawing was studied. The results show that large-sized manganese sulfide inclusions were found at the end of the crack propagation of the sample cross section. There are large-sized manganese sulfide inclusions and slag particles on the inner wall of the crack. It is speculated from the results that slag particles in steel is the main cause of crack initiation, and large-sized manganese sulfide inclusions are the cause of crack propagation. According to the mechanism of crack initiation and propagation,this paper proposes to control the initiation and propagation of cracks by increasing the alkalinity and reduction of the slag and accurately controlling the oxygen content of the refining station.
艾克南, 张盼盼, 赵梦豪, 李成良, 张志明, 付建勋. 1215易切削钢拉拔表面裂纹形成机制分析[J]. 钢铁, 2020, 55(2): 88-94.
AI Ke-nan, ZHANG Pan-pan, ZHAO Meng-hao, LI Cheng-liang, ZHANG Zhi-ming, FU Jian-xun. Analysis of formation mechanism of surface crack of 1215 free-cutting steel during drawing. Iron and Steel, 2020, 55(2): 88-94.
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2020, Vol. 55 
