TH57320B - High-strength galvanized steel sheet and method for the production of high-strength galvanized steel sheet. - Google Patents

Abstract

DC60 (20/01/60) This fabrication provides a high strength galvanized steel sheet with low YP, high BH, excellent anti-curing properties, and excellent corrosion resistance by without The need for bulk additions of expensive elements, such as Mo or Cr, or through special CGL heat cycles and methods for producing such steel plates. galvanized steel sheet with High strength will have C greater than 0.015% and less than 0.1%, Si: 0.3% or lower, Mn: less than 1.90%, P: 0.015% or more and 0.05% or lower, S: 0.03% or lower, sol.Al: 0.01% or more and 0.5% or less, N: 0.005% or less, Cr: less than 0.30%, B: 0.0003% or more and 0.005% or less, and Ti: less than 0.014%. in terms of % by mass, and will correspond to 2.2 less or equal to [Mneq] less than or equal to 3.1 and 0.42 less than or equal to 8 [%P] + 150B * less than or equal to 0.73 The microstructure of steel contains ferrite and second cycle, where the area ratio of the second cycle is 3 to 15%, the area ratio of The preserved martensite and gamma to the second phase area ratio are greater than 70%, and 50% or more of the second phase area ratio is present in the three common points of the grain boundary. 20/01/2017 This invention will provide a high strength galvanized steel sheet with low YP, high BH, excellent anti-curing properties, and excellent corrosion resistance without The need for bulk additions of expensive elements, such as Mo or Cr, or through special CGL heat cycles and methods for producing such steel plates. galvanized steel sheet with High strength will have C: greater than 0.015% and below 0.1%, Si: 0.3% or lower, Mn: less than 1.90%, P: 0.015% or more and 0.05% or lower, S: 0.03% or lower. , sol.Al: 0.01% or more and 0.5% or less, N: 0.005% or less, Cr: less than 0.30%, B: 0.0003% or more and 0.005% or less, and Ti: less than 0.014. % in terms of % by mass, and will correspond to 2.2 (formula) [Mneq] (formula) 3.1 and 0.42 (formula) 8 [%p] + 150B * (formula) 0.73. The microstructure of steel contains ferrite and second cycle, where the area ratio of the second cycle is 3 to 15%, the area ratio of The preserved martensitic and (formula) to the second phase area ratio are greater than 70%, and 50% or more of the second phase area ratio is contained in the three common points of the edge. grain ------------------------------------ This fabrication will be supplied with galvanized steel sheet with High strength with low YP, high BH, excellent anti-curing properties, and excellent corrosion resistance without The need for bulk additions of expensive elements, such as Mo or Cr, or through special CGL heat cycles and methods for producing such steel plates. galvanized steel sheet with High strength will have C: more than 0.015% and below 0.1%, Si: 0.3% or lower, Mn: less than 1.90%, P: 0.015% or more and 0.05% or lower, S: 0.03% or lower. Than, sol.Al: 0.01% or more and 0.5% or less, N: 0.005% or less, Cr: 0.30% or less, B: 0.003% or more and 0.005% or less, and Ti: less. 0.014% in terms of % by mass, and will correspond to 2.2?[Mneq]?3.1 and 0.42?8[%P] + 150B * ? 0.73 The microstructure of Steels contain ferrite and the second phase, where the second phase area ratio is 3 to 15%, the ratio of the martensite area ratio and the preserved y to the phase area ratio. the second is greater than 70%, and 50% or more of the area ratio of the second cycle is present in the common point. Three of the grain boundaries:

Claims (6)

1. Claims (total) which will not appear on the classifieds page :Fever 28/4/16 1.03% or lower, so 1.0003% or more and 0.005% or less, and Ti: lower. 0.014% in terms of % by mass, corresponding to 2.2 ? [Mneq]? 3.1 and 0.42 ? 8 [%P] + 150B * ?0.73, consisting of iron residual and inevitable impurities. , containing ferrite and the second cycle is the microstructure of steel, the area ratio of the second cycle is 3 to 15%, the ratio of the area ratio of the preserved martensite and y to the ratio The second phase area is 70% greater, 50% or more of the second phase area ratio is contained in the three common points of the grain boundary, [Mneq] = [%Mn] + 1.3 [%Cr] + 8 [ %P] + 150B* and B* = [%B] + [%Ti] / 48 x 10.8 x 0.9 + [%A] / 27 x 10.8 x 0.025 will be generated, [%Mn], [% Cr], [%P], [%B], [%Ti], and [%Al] represent the quantities of each type of Mn, Cr, P, B, Ti, and so l.Al, respectively, and In the case of B*? 0.0022, B* = 0.0022 will be generated 1.03% or lower, so 1.1% or lower, and Ti: lower, 0.014% in terms of % by mass, corresponding to 2.2?[Mneq]?3.1 and 0.42 ? 8 [%P] + 150 B*?0.73, consisting of the the rest is iron and the inevitable impurity, consisting of ferrite and the second phase is the microstructure of steel, the second phase area ratio is 3 to 15%, the martensite area ratio and the maintained y to ratio The second cycle area will be 70% or more. 50% or more of the area ratio of the second cycle will be present in the third joint of the grain boundary, [Mneq] = [%Mn] + 1.3 [%Cr] + 8 [%]. P] + 150B* and B* = [%B] + [%Ti] / 48 x 10.8 x 0.9 + [%Al] / 27 x 10.8 x 0.025 will be generated, [%Mn], [%Cr ], [%P], [%B], [%Ti], and [%Al] represent the quantities of each type of Mn, Cr, P, B, Ti, and so l.Al, respectively, and in The case of B*? 0.0022, B* = 0.0022 will be generated. 3. High-strength galvanized steel sheet according to claim 1 or 2, where 0.48 ? 8 [%P] + 150B*?0.73 will be conformed to 1.01% or lower in terms of % by mass 5. Methods for the manufacture of high-strength galvanized steel sheets, consisting of hot-rolling and cold-rolling of steel slabs containing one of the following alloys. of Claims 1 to Articles 4. Tempering of steel plates at annealing temperatures greater than 740 degrees Celsius and below 840 degrees Celsius in the galvanizing line. and continuous galvanizing (CGL), cooling of the steel sheet at an average cooling rate of 2 to 30 °C/s from annealing temperature to dipping in the galvanizing bath, slam dipping. Steel in a galvanized bath for galvanizing. and the cooling of the steel slab up to 100 °C or lower at an average cooling rate of 5 to 100 °C/s. After galvanizing or proceeding with doping treatment after galvanizing, and cooling. Slab down of steel up to 100 °C or lower at an average cooling rate of 5 to 100 °C/s. After alloying treatment 6. Method for producing high strength galvanized steel sheet according to claim 5, where the steel sheet is cooled to 640 °C or lower after hot rolling. at an average cooling rate of 20 °C/s or more and then being coiled at 400 to 620 °C ----------------------- ----------------------------------------- 1. Galvanized steel sheet with The high strength that it contains, is a mixture that is Steel alloy, C:more than 0.015% and less than 0.1%, Si:0.3% or less, Mn: less than 1.90%, P:0.015% or more and 0.05% or less, S:0.03% or less. , so l.Al: 0.01% or more and 0.5% or less, N: 0.005% or less, Cr: less than 0.3%, B: 0.0003% or more, and 0.005% or lower, and Ti: less than 0.014% in terms of % by mass, corresponding to 2.2 ?[Mneq]? 3.1 and 0.42? 8[%P] + 150B * ? 0.73, that comprises the part Residues of iron and inevitable impurities, including Ferrite and the second phase are the microstructure of steel, the second phase area ratio is 3 to 15%, the area ratio of the preserved martensite and y to If the second phase area ratio is greater than 70%, 50% or more of the second phase area ratio is present in the three common points of the grain boundary, [Mneq] = [%Mn] + 1.3 [%Cr] + 8. [%P] + 150B* and B* = [%B] + [%Ti] / 48 x 10.8 x 0.9 + [%A] / 27 x 10.8 x 0.025 will be generated, [%Mn], [ %Cr], [%P], [%B], [%Ti], and [%Al] represent the quantities for each type of Mn, Cr, P, B, Ti, and so l.Al, respectively, and in the case of B*? 0.0022, B* = 0.0022 will be generated 1.03% or lower, so 1.1% or lower, and Ti: below 0.014% in terms of % by mass, corresponding to 2.2. ? [Mneq] ? 3.1 and 0.42 ? 8 [%P] + 150 B * ? 0.73, consisting of iron rest and inevitable impurities, consisting of ferrite and the the second is the microstructure of steel, the second cycle area ratio is 3 to 15%, the area ratio of the preserved martensite and y to The second phase area ratio is greater than 70%. 50% or more of the second phase area ratio is present in the three common points of the grain boundary, [Mneq] = [%Mn] + 1.3 [%Cr] + 8 [ %P] + 150B* and B* = [%B] + [%Ti] / 48 x 10.8 x 0.9 + [%Al] / 27 x 10.8 x 0.025 will be generated, [%Mn], [% Cr], [%P], [%B], [%Ti], and [%Al] represent the quantities of each type of Mn, Cr, P, B, Ti, and so l.Al, respectively, and In the case of B*? 0.0022, B* = 0.0022 will be generated. 3. High strength galvanized steel sheet according to claim 1 or 2, where 0.48 ? 8 [%P] + 150B* ? 0.73 is obtained. Consistency 1.01% or lower in terms of % by mass 5. Method for producing high-strength galvanized steel sheet, consisting of Hot-rolled and cold-rolled alloyed steel slabs according to which claim? One of claims 1 to 4, annealing of steel plates at annealing temperatures above 740°C and below 840°C in galvanizing lines and Continuous Galvanization (CGL), cooling of the steel sheet at an average cooling rate of 2 to 30 °C/s. from annealing temperature to dipping in galvanizing bath, dipping steel slab in galvanized bath for galvanizing, and cooling of Steel slab to 100°C or below with an average cooling rate of 5 to 100C/s. After galvanizing or proceeding with practice with doping of quenching after galvanizing, and cooling of steel slab to 100 °C or less at an average cooling rate of 5 to 100 °C/s after alloying treatment. 6. Method for producing high-strength galvanized steel sheet according to claim 5, where the steel sheet is cooled to 640°C or lower after hot rolling. at an average cooling rate of 20 °C/s or more and then being coiled at 400 to 620 °C.