Abstract:Factors influencing transverse cracks such as compositions of liquid steel, casting powder, mold oscillation, SEN, secondary cooling, and so on, were investigated. The results show that the compositions of liquid steel and the mechanical properties in the low ductility region Ⅲ are the internal reasons which effect transverse cracks; Strong cooling in secondary cooling area and the straightening force are the external cause. Based on these reasons mentioned above, some effective countermeasures were proposed in 400mm ultra-thick slabs: the SEN with concave bottom, the thickness of liquid slag film keeps 8-13mm, soft cooling in secondary cooling area, the surface temperature of slabs in vertical segment keeps above 1100℃, the surface temperature in straighten segment keeps above 940℃. With all these countermeasures, the transverse cracks incidence of the ultra-thick slabs has been reduced to 488%, and the surface quality of slabs has been effectively improved.
朱志远,甄新刚,蒋海涛,李景光,王玉龙,白占禄. 400mm特厚板坯表面横裂纹控制技术[J]. 钢铁, 2011, 46(12): 33-36.
ZHU Zhi-yuan,ZHEN Xin-gang,JIANG Hai-tao,LI Jing-guang,WANG Yu-long,BAI Zhan-lu. Control Technology of the Transverse Cracks in 400mm Ultra-Thick Slabs. Iron and Steel, 2011, 46(12): 33-36.