A high fabrication ultrahigh strength cold-rolling steel plate and a manufacturing method for the same

Title:

A high fabrication ultrahigh strength cold-rolling steel plate and a manufacturing method for the same

Document Type and Number:

Japanese Patent JP6207621

Kind Code:

B2

Abstract:

A high-formability and super-strength cold-rolled steel sheet and a manufacturing method thereof. The weight percentage of its components is: C 0.15-0.25%, Si 1.00-2.00%, Mn 1.50-3.00%, P<0.015%, S‰¤0.012%, Al 0.03-0.06%, N‰¤0.008%, and the rest are Fe and inevitable impurities. The manufacturing method comprises the following steps: 1) smelting and casting; 2) heating to 1170ˆ¼1230°C and performing thermal insulation; 3) performing hot rolling, the finish rolling temperature being 880±30°C, and coiling at 550ˆ¼650°C; and 4) performing acid washing, cold rolling, and annealing, the cold rolling reduction being 40-60%, annealing at 860-920°C, and performing slow cooling to 690-750°C with the cooling rate of 3ˆ¼10°C/s; performing rapid cooling at 240ˆ¼320°C, with the cooling speed ‰¥0°C/s, then heating to 360ˆ¼460°C, and performing thermal insulation for 100ˆ¼500s to cool to the room temperature at last. Finally, a high-formability, low-rebound property and super-strength cold-rolled steel sheet with the yield strength of 600ˆ¼900MPa, the tensile strength of 980ˆ¼1150MPa, the elongation of 17ˆ¼25% is obtained.

Inventors:

Bell Isamu
Wang Li
Feng Wei
Bear wei
Construction army
Hu Hiroi

Application Number:

JP2015542138A

Publication Date:

October 04, 2017

Filing Date:

February 21, 2013

Export Citation:

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