The present disclosure provides a hot-press formed part comprising a plated steel sheet and an aluminum alloy plated layer formed on the plated steel sheet, wherein the aluminum alloy plated layer comprises: an alloying layer (I) formed on the plated steel sheet and containing, by weight %, 5-30% of Al; an alloying layer (II) formed on the alloying layer (I) and containing, by weight %, 30 to 60% of Al; an alloying layer (III) formed on the alloying layer (II) and containing, by weight %, 20-50% of Al and 5-20% of Si; and an alloying layer (IV) formed continuously or discontinuously on at least a part of the surface of the alloying layer (III), and containing 30-60% of Al, wherein the rate of the alloying layer (III) exposed on the outermost surface of the aluminum alloy plated layer is 10% or more.

The present invention relates to a steel sheet for a hot press formed member having excellent coating adhesion, and a method for manufacturing the same. A steel sheet for hot press forming according to one aspect of the present invention is an aluminum alloy plated steel sheet, wherein an average Fe content in a plating layer may be 40 wt % or more, and a concentration gradient of a section having a Fe content of 45 wt % to 80 wt % in the plating layer may 7 wt %/μm or less of a concentration gradient at a section having an Fe content of 45% to 80% in the plating layer in a thickness direction from a surface of the plating layer according to a result of GDS analysis.

The present invention discloses a method for ultra-low temperature forming an ultra-thin curved part of a high-strength aluminum alloy. The method includes the following steps: step 1: selecting a cladding with a suitable thickness according to a wrinkle limit of a sheet; step 2: stacking the sheet and the cladding, then putting into a die, and closing a blank holder; step 3: filling a cavity of a female die with an ultra-low temperature medium to cool the sheet to below −160° C.; step 4: applying a set blank holding force by the blank holder, and enabling a male die to go down to form a thin-walled curved part; and step 5: opening the die and taking out the formed thin-walled curved part. The present invention utilizes the favorable formability of the high-strength aluminum alloy at the ultra-low temperature and the instability resistance of the thick sheet.

Metallic tubular products having improved collapse resistance are disclosed. The metallic tubular products are produced by compressive forming processes. The method comprises identifying the types of stress that can be applied in order to change the residual stress profile of metallic tubular products, such as those that have completed a straightening process, and results in a residual stress profile that improves collapse resistance. The metallic tubular products are subjected to radial compression processing to control the residual stress profile and to enhance collapse resistance. The radial compression process may be used after the tubular product has been subjected to a straightening process.

Roll forming is used for re-shaping an iridium crucible. The crucible is placed on a platen. The platen rotates the crucible while heat is applied by a plurality of torches. A plurality of rollers press on the rotating, heated crucible to re-shape. The roll forming allows for a greater number of repetitions of the re-shaping, increasing the number of uses per expensive re-fabrication of the crucible. The roll forming may provide more exact re-shaping.

The present invention may provide a method of trimming a ultra high strength hot stamping steel sheet using coining, which includes a forming step and a coining step which are simultaneously performed on a hot stamping steel sheet.

The present disclosure provides a hot-press formed part comprising a plated steel sheet and an aluminum alloy plated layer formed on the plated steel sheet, wherein the aluminum alloy plated layer comprises: an alloying layer (I) formed on the plated steel sheet and containing, by weight %, 5-30% of Al; an alloying layer (II) formed on the alloying layer (I) and containing, by weight %, 30 to 60% of Al; an alloying layer (III) formed on the alloying layer (II) and containing, by weight %, 20-50% of Al and 5-20% of Si; and an alloying layer (IV) formed continuously or discontinuously on at least a part of the surface of the alloying layer (III), and containing 30-60% of Al, wherein the rate of the alloying layer (III) exposed on the outermost surface of the aluminum alloy plated layer is 10% or more.

Provided is a steel sheet for a hot press formed member having excellent coating adhesion, and a method for manufacturing the same. A steel sheet for hot press forming is an aluminum alloy plated steel sheet, wherein an average Fe content in a plating layer may be 40 wt % or more, and a concentration gradient of a section having a Fe content of 45 wt % to 80 wt % in the plating layer may 7 wt %/μm or less of a concentration gradient at a section having an Fe content of 45% to 80% in the plating layer in a thickness direction from a surface of the plating layer according to a result of GDS analysis.

A method of forming a hot stamped, die quenched, and die trimmed part is provided. The method includes hot stamping and die quenching a blank with a quench die and forming a die quenched panel. The quench die includes at least one slow-cooling channel. The die quenched panel is die trimmed along the at least one localized soft zone that is adjacent a hard zone. The blank may be formed from a press hardenable steel (PHS), and the at least one soft zone may have a ferritic microstructure and the at least one hard zone may have a martensitic microstructure. The at least one localized soft zone may have a microhardness between about 200 HV and about 250 HV and the hard zone may have a microhardness between about 400 HV and about 500 HV.

A blank (100) includes a main portion (110) that is made of steel having a tensile strength of 1450 MPa or more and a softened portion (120), the ratio of Vickers hardness of the softened portion (120) to the Vickers hardness of the main portion (110) is 0.7 or more and 0.95 or less, and the softened portion (120) is disposed at a position different from a position of the main portion (110) in an in-plane direction. A structural member (200) includes a first member (210), a second member (220), and a weld (W) at which the first member (210) and the second member (220) are welded to each other.