Q420钢连铸坯的质量检验和晶内铁素体形貌分析  

Quality Examination and Analysis on Intragranular Ferrite Morphology for Continuously Cast Q420 Steel Billet

作　　者：吴俊平 潘中德 张迪 张朋彦 张清辉 WU Junping;PAN Zhongde;ZHANG Di;ZHANG Pengyan;ZHANG Qinghui(Nanjing Iron&Steel Co.,Ltd.,Nanjing 210035,Jiangsu China;School of Metallurgical Engineering,Anhui University of Technology,Ma’anshan 243002,Anhui China)

机构地区：[1]南京钢铁股份有限公司,江苏南京210035 [2]安徽工业大学冶金工程学院,安徽马鞍山243002

出　　处：《热处理》2023年第1期22-26,共5页Heat Treatment

摘　　要：通过低倍检验、金相分析和能谱分析等检测了Q420钢连铸坯的质量,即宏观形貌、夹杂物的种类、数量和尺寸以及晶内铁素体的形貌等。结果表明:Q420钢连铸坯的低倍凝固组织主要由细晶区、柱状晶区和等轴晶区组成,等轴晶率为35.1%,且其中心存在C、S的正偏析;Q420钢连铸坯中的非金属夹杂物主要为TiN-Nb、CaS和CaS-Oxide,其尺寸大多≤10μm;晶内铁素体主要呈多边形。The quality of continuously cast Q420 steel billet,that is,macroscopic appearance,type,amount and size of inclusions,as well as morphology of intragranular ferrite were tested with the aid of macro-check,metallographic examination and energy spectrum analysis.The results showed that(a)low-magnification solidification structure of the continuously cast billet was mainly composed of fine grain region,columnar grain region and equiaxed grain region,the percentage of equiaxed grain was 35.1%,and positive segregation of carbon and sulphur existed in its centre;(b)the non-metallic inclusions in the continuously cast Q420 steel billet were largely TiN-Nb,CaS,CaS-Oxide,and their sizes were mostly equal to or less than 10μm;and(c)the intragranular ferrite was mainly in polygonal form.

关 键 词：冷酸蚀 低倍检验 偏析 非金属夹杂物 晶内铁素体 

分 类 号：TG245[金属学及工艺—铸造]