Roasted hardened hot-dip galvanized steel plate with good shape and preparation method thereof

Abstract

The invention belongs to the technical field of steel plate manufacturing, in particular to a hot-dip galvanized steel plate and a preparation method thereof. In order to solve the problems that the hot-dip galvanized steel plate prepared by an existing method is poor in mechanical property, is not good in extension property and the like, the invention provides the hot-dip galvanized steel plate and the preparation method thereof. The hot-dip galvanized steel plate is prepared from the following chemical components in percentage by weight: 0.04-0.08% of C, 0.01-0.04% of Si, 0.10-0.40% of Mn, less than or equal to 0.020% of P, less than or equal to 0.015% of S, 0.015-0.050% of Als, 0.0010-0.0040% of B and the balance of Fe and inevitable impurities. The preparation method for the hot-dip galvanized steel plate comprises the following steps: performing processes of smelting, hot rolling, acid rolling, hot-dip galvanizing and annealing on smelting molten steel, thereby obtaining the hot-dip galvanized steel plate. The hot-dip galvanized steel plate prepared by the preparation method has yield strength of 220-250 MPa, tensile strength of 320-380 MPa, elongation percentage greater thanor equal to 36.0%, n90 greater than or equal to 0.18, r90 greater than or equal to 1.5, BH greater than or equal to 30 MPa, and excellent mechanical properties and forming properties, and can meet using requirements of an automobile outer panel user.

Description

technical field [0001] The invention belongs to the technical field of hot-dip galvanized steel sheet production, and in particular relates to a well-formed bake-hardened hot-dip galvanized steel sheet and a preparation method thereof. Background technique [0002] Baking-hardening hot-dip galvanized steel sheets are widely used in auto parts, which not only require excellent stamping performance and surface appearance quality, but also require certain anti-sag performance and baking hardness to reduce noise during high-speed driving. Production technologies related to bake-hardened steel plates are: [0003] CN 103228808B provides a high-strength bake-hardening cold-rolled steel sheet with excellent bake hardenability, room temperature aging performance and deep drawing processability, and small in-plane anisotropy. The composition is C: 0.0010-0.0040%, Si: 0.005-0.05%, Mn: 0.1-0.8%, P: 0.01-0.07%, S: 0.001-0.01%, Al: 0.01-0.08%, N: 0.0010-0.0050%, Nb: 0.002-0.020%, and Mo...

AI Technical Summary

Problems solved by technology

[0008] The technical problem to be solved by the present invention is: the hot-dip galvanized steel sheet prepared by the existing method has poor mechanical properties, poor elongation performance, and high cost.

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