Prevention of halfway cracks in continuous cast A36 steel slabs containing boron

摘要: The mechanical properties of steels in the temperature range mushy zone are directly related Abstract: formation halfway cracks continuous cast A36 steel slabs containing 17 ppm boron was studied by investigating zero ductility (ZDT), strength (ZST), solidification characteristics, and strain distribution steels. Results show that A36-B slab is attributed to increase both internal crack susceptibility (ZDT ZST) external tensile at front. ZST with (A36-B) without (A36) addition nearly same, but ZDT found 50 oC lower due a considerable content final stage solidification. decrease enlarges cracking results being more prone cracking. In addition, during unbending segments, large strain, resulting from process misalignment deviation supporting rolls, occurs upper part solidified shell, which another reason causing slab. By decreasing P S be less than 150 ppm, respectively, controlling B 10 15 increasing secondary cooling specific water ratio 0.76 0.85 L·kg -1 , restricting roll alignment plus or minus 0.3 mm, almost eliminated.