Patent classifications
C22C18/04
HOT-DIPPED GALVANIZED STEEL SHEET HAVING EXCELLENT BENDING WORKABILITY AND CORROSION RESISTANCE AND MANUFACTURING METHOD THEREFOR
A hot-dipped galvanized steel sheet having excellent bending workability and corrosion resistance and a manufacturing method therefor are provided. A hot-dipped galvanized steel sheet of the present invention comprises: a base steel sheet; a Zn—Mg—Al based plating layer provided on at least one surface of the base steel sheet and including, in wt %, with respect to components other than iron (Fe) diffused from the base steel sheet, 5.1 to 25% of Al and 4.0-10% of Mg, and the remainder of Zn and other inevitable impurities; and an interfacial alloy layer having a Fe—Al—Zn composition formed between the base steel sheet and the plating layer, wherein the interfacial alloy layer has a thickness of 0.5-2 μm and has a dendritic form, the Zn—Mg—Al based plating layer has a Zn—Al—MgZn.sub.2 ternary eutectic structure, a Zn—MgZn.sub.2 binary eutectic structure, and a structure including one or more of an Al single-phase structure having solid-solubilized Zn and a Zn single-phase structure, and agglomerated Al is included in a MgZn.sub.2 structure.
ALUMINUM-BASED ALLOY-COATED STEEL SHEET AND METHOD OF MANUFACTURING SAME
The present disclosure relates to an aluminum-based alloy-coated steel sheet and a method of manufacturing the same and, more particularly, to an aluminum-based alloy-coated steel sheet that can be preferably applied to automotive steel sheets, etc., and a method of manufacturing the same.
An embodiment of the present disclosure provides an aluminum-based alloy-coated steel sheet that includes: a base steel sheet; an Al-based alloy-coated layer formed on at least one surface of the base steel sheet; and a Zn-Al-based coated layer formed on the Al-based alloy-coated layer, including Al: 0.5˜1.0%, and a balance of Zn and unavoidable impurities in percentage by weight, and having an adhesion amount of 3˜12 g/m.sup.2, and a method of manufacturing the aluminum-based alloy-coated steel sheet.
Metallic coated steel product
Provided is a metallic coated steel product which is less likely to experience LME and blowhole formation and is likely to exhibit an improved corrosion resistance at welding heat affected zones. The metallic coated steel product is a hot-dip metallic coated steel product including a steel product and a plating layer that is provided on a surface of the steel product and includes a Zn—Al—Mg alloy layer. In a cross-section of the Zn—Al—Mg alloy layer an area fraction of MgZn.sub.2 phase is from 45 to 75%, a total area fraction of MgZn.sub.2 and Al phases is not less than 70%, and an area fraction of Zn—Al—MgZn.sub.2 ternary eutectic structure is from 0 to 5%; and the plating layer has a predetermined chemical composition.
Metallic coated steel product
Provided is a metallic coated steel product which is less likely to experience LME and blowhole formation and is likely to exhibit an improved corrosion resistance at welding heat affected zones. The metallic coated steel product is a hot-dip metallic coated steel product including a steel product and a plating layer that is provided on a surface of the steel product and includes a Zn—Al—Mg alloy layer. In a cross-section of the Zn—Al—Mg alloy layer an area fraction of MgZn.sub.2 phase is from 45 to 75%, a total area fraction of MgZn.sub.2 and Al phases is not less than 70%, and an area fraction of Zn—Al—MgZn.sub.2 ternary eutectic structure is from 0 to 5%; and the plating layer has a predetermined chemical composition.
Plated steel
A plated steel includes: a steel; and a plating layer that is provided on a surface of the steel, in which the plating layer includes, by mass %, Al: 5.00% to 35.00%, Mg: 2.50% to 13.00%, Fe: 5.00% to 40.00%, Si: 0% to 2.00%, Ca: 0% to 2.00%, and a remainder of Zn and impurities, and in a cross section of the plating layer, the area fraction of a Zn solid-solution Fe.sub.2Al.sub.5 phase in which 5% or more of Zn is solid-soluted is 10% to 60% and the area fraction of a MgZn.sub.2 phase is 10% to 90%.
Plated steel
A plated steel includes: a steel; and a plating layer that is provided on a surface of the steel, in which the plating layer includes, by mass %, Al: 5.00% to 35.00%, Mg: 2.50% to 13.00%, Fe: 5.00% to 40.00%, Si: 0% to 2.00%, Ca: 0% to 2.00%, and a remainder of Zn and impurities, and in a cross section of the plating layer, the area fraction of a Zn solid-solution Fe.sub.2Al.sub.5 phase in which 5% or more of Zn is solid-soluted is 10% to 60% and the area fraction of a MgZn.sub.2 phase is 10% to 90%.
Hot stamped body
A hot stamped body comprising a steel base material and an Al—Zn—Mg-based plating layer formed on a surface of the steel base material, wherein the plating layer has a predetermined chemical composition, the plating layer comprises an interfacial layer positioned at an interface with the steel base material and containing Fe and Al and a main layer positioned on the interfacial layer, the main layer comprises, by area ratio, 10.0 to 85.0% of an Mg—Zn containing phase and 15.0 to 90.0% of an Fe—Al containing phase, the Mg—Zn containing phase comprises at least one selected from the group consisting of an MgZn phase, Mg.sub.2 Zn.sub.3 phase, and MgZn.sub.2 phase, and the Fe—Al containing phase comprises at least one of an FeAl phase and Fe—Al—Zn phase and an area ratio of the Fe—Al—Zn phase in the main layer is 10.0% or less.
Hot dip plated steel sheet having excellent corrosion resistance and workability
Provided is a plated steel sheet applicable for various purposes as in construction materials, household electric appliances, automobiles, etc. and, more particularly, to a hot dip plated steel sheet having excellent corrosion resistance and workability and a manufacturing method therefor.
Hot dip plated steel sheet having excellent corrosion resistance and workability
Provided is a plated steel sheet applicable for various purposes as in construction materials, household electric appliances, automobiles, etc. and, more particularly, to a hot dip plated steel sheet having excellent corrosion resistance and workability and a manufacturing method therefor.
High-strength galvanized steel sheet, high strength member, and method for manufacturing the same
A high-strength galvanized steel sheet includes a steel sheet containing a predetermined component element, a mass ratio of a content amount of Si to a content amount of Mn in the steel (Si/Mn) being 0.2 or more, and a steel structure in which an average grain size of inclusions existing in an area extending from a surface to a position of ⅓ of a sheet thickness is 50 μm or less, and an average nearest distance between ones of the inclusions is 20 μm or more; and a galvanized layer provided on a surface of the steel sheet, in which an amount of diffusible hydrogen contained in the steel is less than 0.25 mass ppm, oxides containing predetermined elements in an outer layer portion of the steel sheet account for 0.010 g/m.sup.2 or more per one surface, and a tensile strength is 1100 MPa or more.