摘要
对厚度为35 mm的热轧Q460GJCZ35钢板进行超声波探伤时发现其内部缺陷过多,不合格。对不合格的钢板进行了扫描电镜检验、能谱分析和硬度测试,以揭示缺陷的性质、成分和分布。结果表明,钢板的内部缺陷主要是微裂纹、含钙和铝的夹杂物、中心偏析及带状组织。采取了某些预防缺陷产生的措施,包括在冶炼和浇注过程中添加防止钢水氧化的装置,改变电磁搅拌电流的强度,加装缓冷罩等,结果,铸坯C类偏析比例提高到了92.6%,钢板的低温冲击吸收能量提高到了155 J,心部碳偏析指数和锰偏析指数降低至1.0,钢板合格率由96.97%提高到了100%。
Hot-rolled 35 mm-thick Q460 GJCZ35 steel plate was inspected for internal defects by the ultrasonic test,and,as a result,it was found that the steel plate was not up to standard because of overproofed internal defects. The unqualified plate was subjected to SEM check,EDS analysis and hardness measurements for the purpose of identifying essence, composition and distribution of the defects. The results indicated that the defects were predominantly microcrack,inclusions containing calcium and aluminum,central segregation and banded structure. A number of precautions,including addition of device preventing the liquid steel from being oxidized,change in intensity of electromagnetic stirring current,addition of retarding cooling cover,have been taken during the smelting and pouring. Following these cautions stated above,percent of C-type segregation in the cast slab increased to 92. 6%,low temperature impact toughness of the plate increased to 155 J,both carbon segregation index and manganese segregation index of the plate core lowered to 1. 0,percent of the qualified plate increased from 96. 97% to 100%.
作者
高军
高峰
赵棪
樊立峰
Gao Jun;Gao Feng;Zhao Yan;Fan Lifeng(Inner Mongolia Baotou Steel Co.,Ltd.,Baotou NeiMonggol 014000,China;School of Materials Science and Engineering,Inner Mongolia University of Technology,Hohhot NeiMonggol 010000,China)
出处
《上海金属》
CAS
北大核心
2018年第4期35-39,共5页
Shanghai Metals
关键词
宽厚板
探伤
缺陷
夹杂物
偏析
wide-heavy plate
flaw detection
defect
inclusion
segregation
