Development of 200 mm Ultra-thick Plate Q235B in Laiwu Steel
GAO Lifu
Abstract：Using 300 mm thickness continuous casting slab, adopting TMCP process, ensuring single pass reduction ratio and cumulative reduction ratio by reasonable distribution of rolling passes, the problems of low compression ratio were solved and the Q235B ultra-thick plates with 200 mm thickness were developed. The thickness tolerance was controlled within ± 1.2 mm. The plate shape is better. The impact absorbed energy of the plate in 1/4 thickness and 1/2 thickness at 0℃are 86-91 J and 55-77 J respectively. The area reduction in thickness direction is 27.0%-31.0%. Poor low-temperature impact toughness was caused by the dendritic crystal that was not completely broken and the part of the coarse Widmannstaetten structure was formed in the near surface.
Keywords：Q235B steelultra-thick plateTMCP processrolling passthickness controlshape control
Publication Date：2015-07-02
Online Publishing Date：2026-05-22(First online date of this platform, not the publication date of the document)
Pages：3( 10-11,16 )