Disclosed is a steel sheet having a predetermined chemical composition and a steel microstructure that contains, in area ratio, 15% or more and 55% or less of polygonal ferrite and 15% or more and 30% or less of martensite, and that contains, in volume fraction, 12% or more of retained austenite, in which the polygonal ferrite, the martensite, and the retained austenite have a mean grain size of 4 μm or less, 2 μm or less, and 2 μm or less, respectively, and each have a mean grain aspect ratio of 2.0 or less, and in which a value obtained by dividing an Mn content in the retained austenite in mass % by an Mn content in the polygonal ferrite in mass % equals 2.0 or more.

The present invention relates to a hot stamped component, a precoated steel sheet used for hot stamping, and a hot stamping process. The hot stamped component of the present invention is provided with a coating of aluminium or an aluminium alloy on at least one surface of the base steel, the coating is produced by interdiffusion between the base steel and a precoating of aluminium or aluminium alloy, and the coating has a thickness of 6 to 26 μm.

A steel alloy workpiece and a method for making a press-hardened steel (PHS) component using the steel alloy workpiece is provided. The steel alloy workpiece includes between about 1.0 and 5.0 weight percent chromium, between about 0.5 and 2.0 weight percent silicon, and a surface having a predetermined imprinted pattern. The imprinted pattern includes one of a plurality of overlapping nested sinusoidal waves and a honey-comb pattern, and ascribes a surface roughness of between about 1.0 microns and 2.5 microns. The method includes providing the steel alloy workpiece, heating the workpieces at a predetermined time and temperature, hot stamping the workpieces into the PHS component, quenching the PHS component at a predetermined quench rate, and e-coating the PHS component. The e-coating is applied directly onto the surface of the PHS component.

A method of making a light weight component is provided. The method including the steps of: forming a first metallic foam core into a desired configuration; applying an external metallic shell to a discrete exterior surface of the first metallic foam core after it has been formed into the desired configuration; arranging the first metallic form core to be adjacent to a second metallic foam core also formed into a desired configuration to form a desired pre-form shape, wherein an applied external metallic shell located on a discrete surface of the second metallic foam core is adjacent to the external metallic shell applied to the discrete exterior surface of the first metallic foam core; and applying an external metallic shell to an exterior surface of the desired pre-form shape.

A method of making a light weight component is provided. The method including the steps of: forming a metallic foam core into a desired configuration; applying an external metallic shell to an exterior surface of the metallic foam core after it has been formed into the desired configuration; forming an inlet opening and an outlet opening in the external metallic shell in order to provide a fluid path through the metallic foam core; and injecting a thermoplastic material into the metallic foam core via the inlet opening.

A method of making a light weight component is provided. The method including the steps of: forming a metallic foam core into a desired configuration; and applying an external metallic shell to an exterior surface of the metallic foam core after it has been formed into the desired configuration.

This glass bonding material (21) is made of a cladding material (1) in which at least a first layer (11) made of an Al-based alloy and configured to be bonded to glass and a second layer (12) made of an Fe—Ni based alloy having a thermal expansion coefficient from 30° C. to 400° C. of 11.5×10.sup.−6 (K.sup.−1) or less are bonded.

The present invention provides a steel sheet plated with aluminum-iron and a preparation method therefor, the steel sheet comprising: a base steel sheet; and a plated layer formed on the surface of the base steel sheet and comprising: an alloyed layer containing at least one of Fe3Al, FeAl(Si), Fe2Al5, and FeAl3; and an aluminum layer formed on the alloyed layer and having a thickness less than 10% of that of the plated layer, wherein the plated layer is 20-35 μm in thickness and contains 1-20 wt % of Mg as measured by GDS at a position 0.1 μm deep from the surface of the plated layer and 10 wt % of oxygen as measured by GDS at a position 0.1 μm deep from the surface of the plated layer.

The present invention provides an aluminum-based plated steel plate used in hot-press forming, the steel plate comprising: a base steel plate; and a plating layer formed on the base steel plate, wherein the plating layer comprises: an alloying layer formed on the surface of the base steel plate and including one or more of Fe 3Al, FeAl(Si), Fe 2Al 5, and FeAl 3; and an aluminum layer formed on the alloying layer and having a thickness less than 10% of the thickness of the plating layer, and the plating layer has a thickness of 5-20 μm and an oxygen content of 10 weight % or less, as measured by GDS, at a depth of 0.1 μm from the surface of the plating layer.

The present invention provides a steel plate plated with an aluminum-iron alloy for hot press forming, the steel plate comprising a base steel sheet and an alloy plated layer formed on the base steel sheet, wherein the alloy plated layer comprises: an alloyed layer (I) formed on the base steel sheet and containing, by weight, Al: 5-30%; an alloyed layer (II) formed on the alloyed layer (I) and containing, by weight, Al: 30-60%; and an alloyed layer (III) formed on the alloyed layer (II) and containing, by weight, Al: 20-50%, wherein the alloy layer (II) has a FeAl (Si) alloy phase dispersed and distributed therein, the FeAl(Si) alloy phase comprising, by weight, Al: 20-50% and Si: 5-20%, and the number density of the FeAl(Si) alloy phase having a circle-equivalent diameter of 5 μm or less is 103/mm2 or more.