A high intensity hot-dip zinc-coated carbon steel sheet excellent in shock-proof fissility and processing section corrosion resistance

摘要

It is a high strength hot dip galvanized steel sheet which has a hot dip galvanized layer on a base steel sheet with a tensile strength of at least 590 mpa characterized by the fact that: The plated sheet comprises a layer of alloy protuberances which contact the base steel plate; the protrusion density of the alloy protrusion layer per unit length of the interface between the base steel plate and the plated layer when viewed from a cross-sectional direction is at least 4 / mm; the maximum diameter in the alloy protuberance layer at said interface is not greater than 100 µm; The base steel plate comprises a refined layer that comes into direct contact with the interface between the base steel plate and the plated layer, a decarburized layer that contacts the refined layer and is present toward the interior of the plate. base steel and an inner layer different from the refined layer and the decarburized layer; and the refined layer, decarburized layer and alloy protrusion layer have at least one type of oxide of themselves and min within the layers.