Macro-Segregation of the Extra Large CC Strand: Its Characteristics and Improvement
From examination of the macro-structures in the extra-large CC strand,it was found that A-segregation even appeared along the perimeter of an entire line around strand,and some center porosities occurred after solidification without any accompanying segregation.Aside from the situation described above,the macro-structures in the top region were similar to those in a conventional ingot while the macro-structures below the top region were similar to those in a continuously cast strand.A-,V-,and centersegregation and center porosities or the pipe (including the top pipe) with the proper combination of the vital few parameters have been remarkably reduced compared with the references.The shrinkage pipe was also greatly reduced from L to 0.23L by top heating and stirring.The internal quality of the extra-large CC strand was improved by decreasing the casting speed and casting temperature as reported in the papers on continuous casting strands.Stirrings could deteriorate or improve the internal quality depending on the conditions of the particular case,which suggests that a proper stirring condition is necessary for the extra-large vertical semicontinuous cating process.The temperature gradient in the final stage of the solidification was found to have a dominant effect on the pipe formation in the center region of the extra-large CC strand.
extra-large CC strand macro-segregation A- V- center-segregation top shrinkage pipe TD11 steel
Kyung-Shik OH Joo-Dong LEE Jeong-Yoon CHOI Seong-Jul KIM
LICC Research Project Team,Engineering Solution Center,Technical Research Labs,POSCO,6261 Donghaeanro,Namgu,Pohang,Gyeongbuk,Korea
国际会议
the 6th International Congress on the Science and Technology of Steelmaking,ICS2015(第六届国际炼钢科技大会)
北京
英文
484-486
2015-05-12（万方平台首次上网日期，不代表论文的发表时间）