| 摘要 |
<p>Dual phase steel sheet is made using a time/temperature cycle including a soak at about AC1+45°F to AC1+135°F and a hold at 850-940F, where the steel has the composition in weight percent, carbon: 0.02-0.20; aluminum: 0.010-0.150; titanium: 0.01 max; silicon: 0.5 max; phosphorous: 0.060 max; sulfur: 0.030 max; manganese: 0.8-2.40; chromium: 0.03-1.50; molybdenum: 0. 03 -1.50; with the provisos that the amounts of manganese, chromium and molybdenum have the relationship: (Mn + 6Cr + 10 Mo) = at least 3.5%. The sheet is preferably in the form of a strip suitable for coating in a continuous galvanizing or galvannealing line, and the product is predominantly ferrite and martensite. The strip may be galvanized or galvannealed at a temperature within thirty degrees F of the temperature of the bath.</p> |
