Patent classifications
B21D22/02
COATED STEEL SHEET WITH THIN ALUMINIUM ALLOY COATING AND COATING METHOD THEREOF
The present invention relates to a coated steel sheet having a thin aluminium alloy coating and a coating method thereof The coated steel sheet of the present invention is used for hot stamping. The coating thickness of the coated steel sheet is 5˜14 μm, wherein the aluminium alloy coating comprises a FeAlSi inhibitive layer adjacent to a substrate steel sheet and an Al alloy layer outside the FeAlSi inhibitive layer, wherein the thickness of the FeAlSi inhibitive layer is no more than 60% of the coating thickness and is 1.5˜6.0 μm. The diameters of Kirkendall voids within 2 μm from an interface between the FeAlSi inhibitive layer and the substrate steel to the interior of the substrate steel are no more than 2.5 μm, wherein the number of Kirkendall voids with a diameter of no less than 0.5 μm and no more than 2.5 μm does not exceed 15 per 35 μm. The present invention also discloses a coating method for coating a thin aluminium alloy coating on a substrate steel sheet for hot stamping. It can eliminate skip coating and enable a hot stamped component obtained by the coated steel sheet to have excellent resistance spot welding performance.
PRE-AGEING SYSTEMS AND METHODS USING MAGNETIC HEATING
Systems and methods of pre-ageing of a metal strip during metal processing include passing the metal strip adjacent a magnetic rotor of a reheater. The systems and methods also include heating the metal strip through the magnetic rotor by rotating the magnetic rotor. Rotating the magnetic rotor induces a magnetic field into the metal strip such that the metal strip is heated.
METHODS OF FORMING AND STAMPING TAILOR FRICTION STIR WELDED BLANKS WITH ENHANCED EDGE STRETCH
A stamped part includes a first blank, a second blank, and a weld joining the first blank to the second blank. The weld includes opposing ends. At least one of the opposing ends of the weld is recessed from adjacent edges of the first and second blanks.
METHODS OF FORMING AND STAMPING TAILOR FRICTION STIR WELDED BLANKS WITH ENHANCED EDGE STRETCH
A stamped part includes a first blank, a second blank, and a weld joining the first blank to the second blank. The weld includes opposing ends. At least one of the opposing ends of the weld is recessed from adjacent edges of the first and second blanks.
FOIL TRANSFER DEVICE
A foil transfer device which transfers foil onto a sheet is disclosed herein. When a nip/release mechanism moves a first roller and starts causing a foil film to be pressed against a confined surface region on a sheet, located apart from a leading edge of the sheet, a controller executes: a first process of causing a conveyor roller to start conveyance of the sheet, while the first roller is positioned in a separate position; a second process of causing the conveyor roller to stop conveyance of the sheet before a foil transfer area reaches a transfer position; a third process of causing the nip/release mechanism to start moving the first roller from the separate position to a nipping position while the conveyance of the sheet is stopped; and a fourth process of causing the conveyor roller to restart conveyance of the sheet before the first roller reaches the nipping position.
HIGH-PERFORMANCE THERMOFORMED COMPONENT PROVIDED WITH COATING, AND MANUFACTURING METHOD THEREFOR
A high-performance thermoformed component provided with a coating, and a manufacturing method therefor. The thermoformed component comprises a substrate and a coating thereon. The substrate comprises the following ingredients in percentage by weight: 0.01-0.8% of C, 0.05-1.0% of Si, 0.1-5% of Mn, 0.001-0.3% of P, 0.001-0.1% of S, 0.001-0.3% of Al, 0.001-0.5% of Ti, 0.0005-0.1% of B, 0.001-0.5% of Nb, 0.001-0.5% of V, and the remainder being Fe and other unavoidable impurities. The appearance of the thermoformed component has no color difference and no mottling. The surface oxygen content of the thermoformed component is 0.1-20 wt. %, and the ratio of the standard deviation to the average value of the surface oxygen content satisfies: 0<standard deviation of oxygen content/average value of oxygen content ≤0.3. In the manufacturing method, a coated steel plate that has undergone heat treatment, transfer processing, and hot stamping is not treated with oil.
HIGH-PERFORMANCE THERMOFORMED COMPONENT PROVIDED WITH COATING, AND MANUFACTURING METHOD THEREFOR
A high-performance thermoformed component provided with a coating, and a manufacturing method therefor. The thermoformed component comprises a substrate and a coating thereon. The substrate comprises the following ingredients in percentage by weight: 0.01-0.8% of C, 0.05-1.0% of Si, 0.1-5% of Mn, 0.001-0.3% of P, 0.001-0.1% of S, 0.001-0.3% of Al, 0.001-0.5% of Ti, 0.0005-0.1% of B, 0.001-0.5% of Nb, 0.001-0.5% of V, and the remainder being Fe and other unavoidable impurities. The appearance of the thermoformed component has no color difference and no mottling. The surface oxygen content of the thermoformed component is 0.1-20 wt. %, and the ratio of the standard deviation to the average value of the surface oxygen content satisfies: 0<standard deviation of oxygen content/average value of oxygen content ≤0.3. In the manufacturing method, a coated steel plate that has undergone heat treatment, transfer processing, and hot stamping is not treated with oil.
HOT-STAMPING FORMED BODY
A hot-stamping formed body has a predetermined chemical composition and includes microstructure which includes residual austenite of which an area ratio is 10% or more and less than 20%, Among grain boundaries of crystal grains of bainite and tempered martensite a ratio of a length of a grain boundary having a rotation angle in a range of 55° to 75° to a total length of a grain boundary having a rotation angle in a range of 4° to 12°, a grain boundary having a rotation angle in a range of 49° to 54°, and the grain boundary having a rotation angle in, a range of 55° to 75° to the <011> direction as a rotation axis is 30% or more.
High-strength medium manganese steel for warm stamping and method for manufacturing same
The present invention relates to high-strength medium manganese steel for warm stamping, which contains 3-10 wt % of manganese (Mn), 0.05-0.3 wt % of carbon (C), and 0.1-1.0 wt % of silicon (Si) as components thereof, with the balance being iron (Fe) and unavoidably contained impurities. The present invention performs heat treatment at the low austenitizing temperature of medium manganese steel, and thus has the effect of reducing the high thermal energy consumption of the prior art hot stamping process. Furthermore, the present invention does not require an additional temperature process, and can obtain high strength by only slow cooling such as air cooling outside a mold without performing cooling at high rate inside the mold, and thus has the effects of simplifying a process and improving manufacturing efficiency.
Method of creasing sheets
The invention relates to a method of creasing sheets (12) by using a creasing tool (14, 20, 21) cooperating with a counter element (22, 23), comprising the following steps: a creasing plate blank (24′) is provided with at least one creasing projection (26) by plastically deforming the material of the blank (24′) so as to form a creasing plate (24), the creasing plate (24) is mounted to a creasing tool (14, 20, 21), sheets (12) to be provided with at least one crease are advanced through a gap between the creasing tool (14, 20, 21) and the counter element (22, 23).