STEEL SHEET FOR CAN, AND PROCESS FOR PRODUCING SAME

摘要

The present invention provides a steel sheet for cans which has high strength and high processability, characterized by containing, in terms of mass%, 0.070-0.080%, excluding 0.080%, C, 0.003-0.10% Si, 0.51-0.60% Mn, etc. and by having, in a rolling-direction cross-section thereof, an average crystal-grain diameter of 5 µm or more and a crystal-grain elongation rate of 2.0 or less. The steel sheet is further characterized in that the hardness difference obtained by subtracting the average Vickers hardness of a cross-section ranging from the surface to a depth of 1/8 the sheet thickness from the average Vickers hardness of a cross-section ranging from a depth of 3/8 the sheet thickness to a depth of 4/8 the sheet thickness is 10 points or more and/or the hardness difference obtained by subtracting the maximum Vickers hardness of the cross-section ranging from the surface to a depth of 1/8 the sheet thickness from the maximum Vickers hardness of the cross-section ranging from a depth of 3/8 the sheet thickness to a depth of 4/8 the sheet thickness is 20 points or more. The steel sheet is furthermore characterized by having a tensile strength of 500 MPa or higher and an elongation at fracture of 10% or higher. Also provided is a process for producing the steel sheet. This steel sheet for cans, which has high strength and high processability, is suitable for use as a material for easy-to-open cans.