Abstract: An aluminum-magnesium alloy sheet having a high strength prior to baking treatment, and having a high bake softening resistance. Contains, as a percentage of mass, 2-5% magnesium, more than 0.05% and 1.5% or less iron, 0.05-1.5% manganese, and crystal grain refiner, the remainder comprising aluminum and inevitable impurities, and among the inevitable impurities, less than 0.20% silicon being contained, the total amount of iron and manganese being greater than 0.3%, the amount of iron dissolved in solid solution being 50 ppm or greater, 5000 or more intermetallic compounds with a circle-equivalent diameter of 1-6 ?m existing per square millimeter, and the average diameter of the recrystallized grains being 20 ?m or smaller.

Abstract: An aluminum alloy sheet having excellent press formability and stress corrosion cracking resistance, comprises 3.3 to 3.6 percent by weight of Mg and 0.1 to 0.2 percent by weight of Mn, furthermore, 0.05 to 0.3 percent by weight of Fe and 0.05 to 0.15 percent by weight of Si, and the remainder comprises Al and incidental impurities, wherein the sizes of intermetallic compounds is 5 ?m or less, the recrystallized grain size is 15 ?m or less in the region at a depth of 10 to 30 ?m below the sheet surface, and the surface roughness is Ra 0.2 to 0.7 ?m.

Abstract: An aluminum alloy sheet is manufactured by preparing a slab having a thickness of 5 to 15 mm with a continuous casting machine by a continuous casting process using molten alloy containing 0.40% to 0.65% of Mg, 0.50% to 0.75% of Si, 0.05% to 0.20% of Cr, and 0.10% to 0.40% of Fe, a remainder being Al; winding the slab into a coil; cold-rolling the slab into a sheet; subjecting the sheet to solution heat treatment in such a manner that the sheet is heated to a temperature of 530° C. to 560° C. at a heating rate of 10° C./sec or more and then maintained at the temperature for five seconds or more; quenching the sheet with water; coiling up the sheet; maintaining the sheet at a temperature of 60° C. to 110° C. for 3 to 12 hours; and then cooling the sheet to room temperature.

Abstract: High strength aluminum alloy sheet having superior surface roughening and formability suitable for home electrical appliances and automobile outer panels and other structural materials and a method of production of the same are provided. High strength aluminum alloy sheet having a chemical composition containing Mg: 2.0 to 3.3 mass %, Mn: 0.1 to 0.5 mass %, and Fe: 0.2 to 1.0 mass %, having a balance of unavoidable impurities and Al, and having an Si among the unavoidable impurities of less than 0.20 mass % and having an average circle equivalent diameter of intermetallic compounds of 1 ?m or less, having an area ratio of intermetallic compounds of 1.2% or more, having an average diameter of recrystallized grains of 10 ?m or less, and having a tensile strength of 220 MPa or more.

Abstract: An aluminum alloy sheet for motor vehicles is produced by casting a melt, containing 3.0-3.5 mass % Mg, 0.05-0.3 mass % Fe, 0.05-0.15 mass % Si, and less than 0.1 mass % Mn, a balance substantially being inevitable impurities and Al, into a slab having a thickness of 5 to 15 mm in a twin-belt caster so that cooling rate at ¼ depth of thickness of the slab is 20 to 200° C./sec; winding the cast thin slab into a coiled thin slab subjected to cold rolling with a roll having a surface roughness of 0.2 to 0.7 ?m Ra at a cold rolling reduction of 50 to 98%; subjecting the cold rolled sheet to final annealing either continuously in a CAL at a holding temperature of 400 to 520° C. or in a batch annealing furnace at a holding temperature of 300 to 400° C.; and subjecting the resulting sheet to straightening with a leveler.

Abstract: High strength aluminum alloy sheet having superior surface roughening and formability suitable for home electrical appliances and automobile outer panels and other structural materials and a method of production of the same are provided. High strength aluminum alloy sheet having a chemical composition containing Mg: 2.0 to 3.3 mass %, Mn: 0.1 to 0.5 mass %, and Fe: 0.2 to 1.0 mass %, having a balance of unavoidable impurities and Al, and having an Si among the unavoidable impurities of less than 0.20 mass % and having an average circle equivalent diameter of intermetallic compounds of 1 ?m or less, having an area ratio of intermetallic compounds of 1.2% or more, having an average diameter of recrystallized grains of 10 ?m or less, and having a tensile strength of 220 MPa or more.

Abstract: An aluminum alloy sheet is manufactured by preparing a slab having a thickness of 5 to 15 mm with a continuous casting machine by a continuous casting process using molten alloy containing following components: 0.40% to 0.65% of Mg, 0.50% to 0.75% of Si, 0.05% to 0.20% of Cr, and 0.10% to 0.40% of Fe, remainder being Al, the components being essential elements, and optionally up to 0.15% Cu, 0.10% Ti; winding the slab into a coil; hot-rolling or directly coiling up the slab; cold-rolling the slab into a sheet; subjecting the sheet to solution heat treatment with a continuous annealing furnace; and then pre-aging the sheet. The aluminum alloy sheet has the same composition as the molten alloy, has a grain size of 10 to 25 ?m, is superior in bake hardenability, bendability, and surface quality (orange peel), and can be manufactured with low cost.

Abstract: An aluminum alloy sheet having excellent press formability and stress corrosion cracking resistance, comprises 3.3 to 3.6 percent by weight of Mg and 0.1 to 0.2 percent by weight of Mn, furthermore, 0.05 to 0.3 percent by weight of Fe and 0.05 to 0.15 percent by weight of Si, and the remainder comprises Al and incidental impurities, wherein the sizes of intermetallic compounds is 5 ?m or less, the recrystallized grain size is 15 ?m or less in the region at a depth of 10 to 30 ?m below the sheet surface, and the surface roughness is Ra 0.2 to 0.7 ?m.

Abstract: An aluminum-magnesium alloy sheet having a high strength prior to baking treatment, and having a high bake softening resistance. Contains, as a percentage of mass, 2-5% magnesium, more than 0.05% and 1.5% or less iron, 0.05-1.5% manganese, and crystal grain refiner, the remainder comprising aluminum and inevitable impurities, and among the inevitable impurities, less than 0.20% silicon being contained, the total amount of iron and manganese being greater than 0.3%, the amount of iron dissolved in solid solution being 50 ppm or greater, 5000 or more intermetallic compounds with a circle-equivalent diameter of 1-6 ?m existing per square millimeter, and the average diameter of the recrystallized grains being 20 ?m or smaller.

Abstract: To provide an aluminum alloy sheet with excellent formability at high temperatures and high speeds with a reduced amount of cavities after forming and a method of production of the same. An aluminum alloy sheet consisting of 2.0-8.0 wt % of Mg, 0.06-0.2 wt % of Si, 0.1-0.5 wt % of Fe, 0.1-0.5 wt % of Mn, and the balance of Al and unavoidable impurities, wherein a density of inter-metallic compounds having an equivalent circle diameter of 1 to 5 ?m is 5000/mm2 or more and an average crystal grain size is 20 ?m or less. A method of production of an aluminum alloy sheet comprising the steps of casting an alloy melt having the above described composition by a twin belt casting machine at a cooling rate of 20 to 150° C.

Abstract: [PROBLEMS] To provide a method for producing an aluminum alloy sheet excellent in bake-hardenability and hemmability at a low cost by the employment of a very short production process. [MEANS FOR SOLVING PROBLEMS] A method for producing an aluminum alloy sheet, which comprises providing an aluminum alloy melt having a chemical composition, in wt %, that Mg: 0.30 to 1.00%, Si: 0.30 to 1.20%, Fe: 0.05 to 0.50%, Mn: 0.05 to 0.50%, Ti: 0.005 to 0.10%, optionally further one or more of Cu: 0.05 to 0.70% and Zr: 0.05 to 0.40%, and the balance: Al and inevitable impurities, casting the alloy melt into a slab having a thickness of 5 to 15 mm by the twin belt casting method with a cooling speed at ¼ of the thickness of the slab of 40 to 150° C./s, winding up a coil, subjecting the coil to a homogenizing treatment, cooling the resultant coil to a temperature of 250° C. or lower with a cooling speed of 500° C./hr or more, followed by cold rolling, and then subjecting the resulting product to a solution treatment.

Abstract: [Objectives] Strengthening, cost reduction, and improvement of press formability and bake hardenability of aluminum alloy sheets. [Means for achieving objectives] A manufacturing method for Al—Mg—Si aluminum alloy sheet with excellent bake hardenability, characterized by twin belt casting a molten Al—Mg—Si aluminum alloy containing Mg: 0.3-1.0 wt %, Si: 0.3-1.5 wt %, Cu: 1.0 wt % or below (including 0%), and Fe: 1.2 wt % or below (including 0%), and containing Mn: 0.1-0.7 wt % and/or Cr: 0.1-0.3% according to need, and the remnant being Al at an average cooling rate of 20 degrees C. or above, and at that time, making the temperature of the ingot as it comes out of the casting machine 250 degrees C. or below, and then rolling to the final sheet thickness by cold rolling only and without homogenization or hot rolling, and solution treatment being done in a continuous annealing furnace.

Abstract: The invention offers an aluminum alloy plate with excellent press-formability and continuous resistance spot weldability, and a method of manufacturing such a plate. The aluminum alloy plate comprises, in % by mass, 0.3-1.0% of Mg, 0.3-1.2% of Si, 0.10-1.0% of Fe and 0.05-0.5% of Mn; where Fe+Mn?0.2%; the remainder consisting of Al and unavoidable impurities; wherein an average value of recrystallized grain size is 25 ?m or less; and at least 5000 particles/mm2 of intermetallic compounds with a circle-equivalent diameter of 1-6 ?m exist. It can further contain 0.5-1.0% of Cu, 0.1-0.4% of Zr, 0.05% or less of Ti or 0.05% or less of Ti together with 0.01% or less of B. The invention also offers a method of manufacturing an aluminum alloy plate comprising steps of pouring a melt consisting of the above composition into an opposing rotating belt caster that is forcibly cooled; casting the melt at a cooling rate of 40-90° C.

Abstract: An aluminum alloy sheet for automotive use is provided which comprises a starting aluminum alloy sheet which has an alloy composition containing from 2 to 6% by weight of Mg, 0.15 to 1.0% by weight of Fe and from 0.03 to 2.0% by weight Mn, and a surface layer disposed over one surface of the starting alloy sheet to be pressed against electrodes for use in welding, the surface layer containing a particulate intermetallic compound has a particle diameter of 0.5 &mgr;m or more and a density of 4,000 pieces of particles per one mm2 or more. The product alloy sheet ensure least deformation of an electrode and stable weldability by means of continuous resistance spot welding.

Abstract: A continuously cast and rolled sheet of an aluminum alloy having Mg in a content of 3 to 6% by weight is annealed, followed by strain correction, heat and hold treatment at a given temperature between 240° C. and 340° C. for one hour or more, and slowly cooling treatment, to thereby provide an aluminum alloy sheet having enhanced resistance to stress corrosion cracking and improved shape fixability. The slowly cooling treatment is carried out at a cooling rate chosen from a preset cooling zone corresponding to a present temperature zone S defined in obliquely lined surround form in the accompanying drawing.