PRODUCTION OF HOT ROLLED MULTILAYER STEEL PLATE HAVING SURFACE LAYER COMPOSED OF AUSTENITIC STAINLESS STEEL AND EXCELLENT IN CORROSION RESISTANCE AND DEEP DRAWABILITY

摘要

PURPOSE: To stably produce a hot rolled multilayer steel plate excellent in corrosion resistance and deep drawability at a low cost by subjecting a steel slab consisting of surface layer parts composed of austenitic stainless steel and an inner layer part composed of a steel with specific composition to specific hot rolling. ;CONSTITUTION: A steel slab is constituted of surface layer parts composed of austenitic stainless steel having a thickness of 2-30%, per side, of the whole plate thickness and an inner layer part composed of a steel with specific composition. The steel of the inner layer part has a composition consisting of, by weight, 0.0005-0.0150% C, 0.0005-0.0200% N, P, Si, Al, Ti, Nb, and the balance Fe with inevitable impurities and further containing, if necessary, either or both of 0.0002-0.0060% B and 0.005-0.500% Mo and satisfying the relations in 30≥80×P+7×Si+20mAl≥3 and 8.0≥Ti/(4×C +3.4×N)+Nb/(7.7×C)≥0.4. This steel slab is hot-rolled at 920°C finishing temp. Then, the resulting hot rolled plate is subjected to hot rolled plate annealing at 850-1250°C. By this method, the hot rolled multilayer steel plate having surface layers composed of austenitic stainless steel combining high corrosion resistance, high workability, and high deep drawability can be obtained.;COPYRIGHT: (C)1993,JPO&Japio