HIGHLY EFFICIENT PRODUCTION METHOD OF STEEL PLATE WITH EXCELLENT COLLISION RESISTANCE

摘要

PROBLEM TO BE SOLVED: To efficiently produce a steel plate with excellent collision resistance.;SOLUTION: In a highly efficient production method of a steel plate with excellent collision resistance, a steel raw material having a specified composition of components is heated, next the steel raw material is rolled so as to produce the steel plate with the condition that a cumulative rolling reduction ratio at 900°C or less is 20% or more, and rolling finishing temperature is Ar₃ to 850°C, while the steel raw material is quickly cooled at average cooling speed of the steel plate of 15- 300°C/s, in a part of or total paths during rolling, after the rolling is finished, the steel plate is cooled with the condition that cooling start temperature is Ar₃ or more in terms of average temperature of the steel, average cooling speed is 10°C/s or more, and cooling stop temperature is (Ar₃-90)°C to (Ar₃-70)°C as cooling of the first step, and next as cooling of the second step starting one to four seconds later after cooling of the first step is finished, the steel plate is cooled with the condition that average cooling speed is 10°C/s or more, and cooling stop temperature is 300°C to 650°C.;COPYRIGHT: (C)2016,JPO&INPIT