Patent ID: 9073292
Filing Date: 2015-07-07
Classification: B32B,C21D,C22C,C23C,Y10T

Abstract:
1. A high strength galvanized steel sheet having excellent formability, comprising a steel sheet which is a base sheet and a galvanized layer on a surface of the steel sheet, wherein the steel sheet is a high strength steel sheet which has a composition comprising, by mass %, 0.08 to 0.15% of C, 0.5 to 1.5% of Si, 0.5 to 1.5% of Mn, 0.1% or less of P, 0.01% or less of S, 0.01 to 0.1% of Al, 0.005% or less of N, and the balance Fe with inevitable impurities, and a microstructure composed of 75 to 90% of a ferrite phase as a main phase and 10 to 25% of a second phase including at least pearlite in terms of an area fraction with respect to the entire microstructure; an average grain size of the pearlite is 5 μm or smaller; and the pearlite has an area fraction of 70% or greater with respect to the total area of the second phase.