40MnB钢偏析形成带状组织的机理研究.pdfVIP

第 27 卷第 6 期 　 物理测试 　Vol . 27 ,No . 6 2009 年11月 　 　 Phy sics Examination and Testing Nov . 2009 40Mn B 钢偏析形成带状组织的机理研究 朱施利 , 　胡文豪 (杭州钢铁集团技术中心 ,浙江 杭州 3 10022) 摘 　要 : 观测和分析了40MnB 钢铸坯断面不同位置的枝晶偏析形貌 ,并对枝晶和枝晶间成分偏析进行微观检测 ; 研究了不同热轧压下量时显微组织的偏析形态 ;借助扩散方程讨论了枝晶间距和热轧显微组织对带状组织的影 响 。结果表明:40MnB 钢铸坯由表面到中心偏析逐渐加重 ,C 、Mn 元素在枝晶间偏析 ,铸坯中心处 Mn 元素偏析严 重 ;偏析间距决定着消除带状组织的难易;减轻铸坯枝晶偏析和热轧组织偏析有利于消除带状组织 。 关键词 : 40 MnB ;偏析 ;带状组织机理 中图分类号 : T G113 . 1 　　文献标识码 :A 　　文章编号 :100 10777 (2009) Research on Mechanism of Forming Banded Structure f or Segregation of 40Mn B Steel ZHU Shili , 　HU Wenhao ( Technology Cent er , Hangzhou Iron St eel Group Co , Hangzhou 3 10022 , Zhej iang , China) Abstract : Dendritic segregation morp holo gy locating at different cro ss section s of ca sting billet was ob served and an alyzed , and segregation microcont ent of dendrit e and int er dendrit e in 40MnB st eel were examined ; Segregation mi cro st ruct ure was researched at different hot rolling reduction s ; The effect of dendritic di st ance and hot rolling micro st ruct ure on banded st ruct ure was di scu ssed by diffu se equation . The result s show t hat t he segregation i s aggravat ed gradually f rom ext erior to cent er in ca sting billet of 40MnB st eel , t he element C and Mn segregat e in int er dendrit e , and esp ecially t he lat er , at t he cent er of ca sting billet ; The difficult y and eliminating banded st ruct ure dep ends on segregation di st ance ; It’s advant aged to eliminat e banded st ruct ure t hat dendritic segregat