| 摘要 |
<p>PURPOSE: A high-strength thick plate with improved low-temperature shock toughness and a method of manufacturing the same are intended to provide a complex structure having fine bainite on fine ferrite matrix. CONSTITUTION: A method of manufacturing a thick plate with high-strength and improved low-temperature shock toughness comprises next steps. Slab is re-heated. The re-heated board is first rolled at over a temperature to stop austenite recrystallization. The first rolled board is second rolled at below the temperature to stop austenite recrystallization. The second rolled board is cooled. The slab consists of C of 0.05~0.1 weight%, Si of 0.2~0.4 weight%, Mn of 1.2~1.6 weight%, P of 0.015 weight% or less, S of 0.005 weight% or less, Al of 0.02~0.05 weight%, Ti of 0.005~0.015 weight%, Nb of 0.01~0.04 weight%, Ni of 0.2~0.4 weight%, N of 60ppm or less, Fe and other inevitable impurities.</p> |
