High-strength multiphase tinned steel raw plate and manufacturing method therefor

Abstract

Disclosed are a high-strength multiphase steel tinned raw plate and a manufacturing method therefor, wherein the mass percentages of the components of the multiphase steel tinned raw plate are: 0.081%-0.14% of C, 0.2%-0.8% of Mn, 0.01%-0.09% of Al, 0.01%-0.03% of P, 0.002%-0.015% of N, also containing one or more than one of 0.001%-0.005% of B, 0.005%-0.05% of Cr, 0.001%-0.1% of Ti, 0.001%-0.2% of Nb, 0.005%-0.03% of Cu, 0.001%-0.008% of Mo, and the balance of Fe and other inevitable impurities; and satisfy: 0.21%≤Mn+1.3 Cr+3.2 Mo+0.5 Cu≤0.91%. The tinned raw plate has a structure comprising ferrite grains, pearlite, martensite and cementite particles, wherein the total volume fraction of the pearlite, martensite and cementite particles is 5%-20%, the volume fraction of the martensite is 1%-5%, and the martensite has a solid solution content of carbon of ≥0.07%. The tinned raw plate has a high strength and better elongation, and can be used to produce a can body, a can bottom, an easy-open end and a twist-off cap, etc. of a three-piece can which has higher requirements for strength and elongation.