A press hardening method including the following steps: A. the provision of a steel sheet for heat treatment being optionally coated with a zinc- or aluminum-based pre-coating, B. the flexible rolling of the steel sheet in the rolling direction so as to obtain a steel sheet having a variable thickness, C. the cutting of the rolled steel sheet to obtain a tailored rolled blank, D. the deposition of a hydrogen barrier pre-coating over a thickness from 10 to 550 nm, E. the heat treatment of the tailored rolled blank to obtain a fully austenitic microstructure in the steel, F. the transfer of the tailored rolled blank into a press tool, G. the hot-forming of the tailored rolled blank to obtain a part having a variable thickness,H. the cooling of the part having a variable thickness obtained at step G).

A press hardening method including: A. provision of a steel sheet for heat treatment, being optionally precoated with a zinc- or aluminum-based pre-coating, B. deposition of a hydrogen barrier pre-coating comprising chromium and not comprising nickel over a thickness from 10 to 550 nm, C. cutting of the precoated steel sheet to obtain a blank, D. heat treatment of the blank at a furnace temperature from 800 to 970° C., during a dwell time from 1 to 12 minutes, in an atmosphere having an oxidizing power equal or higher than that of an atmosphere consisting of 1% by volume of oxygen and equal or smaller than that of an atmosphere consisting of 50% by volume of oxygen, such atmosphere having a dew point between −30 and +30° C., E. transfer of the blank into a press tool, F. hot-forming at a temperature from 600 to 830° C. to obtain a part, G. cooling of the part obtained at step E).

Provided is a forming system that expands and deforms a metal material to perform forming, the forming system including: a forming device that performs the forming; and at least one transport device that transports the metal material, in which the transport device transports the metal material to the forming device in a held state, in a case where a pretreatment device that performs pretreatment for the forming is present, the transport device transports the metal material to the pretreatment device in a held state, and during a period from a transport process in which the metal material is transported to any of devices by the transport device to a treatment process performed by any of the devices, at least one of the transport device and any of the devices continues holding the metal material.

The present invention relates to a steel material including, in mass %: 0.310≤C≤0.410; 0.001≤Si≤0.35; 0.45≤V≤0.70; Cr≤6.00; 6.25≤Mn+Cr; Mn/Cr≤0.155; Cu+Ni≤0.84; 0.002≤P≤0.030; 0.0003≤S≤0.0060; P+5S≤0.040; 2.03<Mo<2.40; 0.001≤Al≤0.050; and 0.003≤N≤0.050, with the balance being Fe and unavoidable impurities.

The present invention relates to a steel material including, in mass %: 0.310≤C≤0.410; 0.001≤Si≤0.35; 0.45≤V≤0.70; Cr≤6.00; 6.25≤Mn+Cr; Mn/Cr≤0.155; Cu+Ni≤0.84; 0.002≤P≤0.030; 0.0003≤S≤0.0060; P+5S≤0.040; 2.03<Mo<2.40; 0.001≤Al≤0.050; and 0.003≤N≤0.050, with the balance being Fe and unavoidable impurities.

Embodiments of the present disclosure provides an aluminum alloy-plated steel sheet having high surface quality and weldability, a hot-formed member, and methods for manufacturing the aluminum alloy-plated steel sheet and the hot-formed member. The aluminum alloy-plated steel sheet includes: a base steel sheet; and an aluminum alloy plating layer formed on the base steel sheet, wherein the aluminum alloy plating layer includes, by weight %, Zn: 21% to 35%, Si: 1% to 6.9%, Fe: 2% to 12%, and the balance of Al and inevitable impurities.

A seamless steel pipe of the present invention is a seamless steel pipe having a composition including, in mass %, C: 0.01 to 0.12%, Si: 0.01 to 0.8%, Mn: 0.10 to 2.00%, P: 0.050% or less, S: 0.040% or less, Al: 0.010 to 0.100%, Cu: 0.03 to 0.80%, Ni: 0.01 to 0.50%, Mo: 0.01 to 0.20%, Sb: 0.002 to 0.50%, Cr: 0.004% or less, W: 0.002% or less, and the balance Fe and incidental impurities, and a structure including a ferrite phase having an area percentage of 50 to 65%, a pearlite phase having an area percentage of 2% or less, and one or both of a bainite phase and a martensitic phase representing the remainder, the seamless steel pipe having a yield strength of 230 MPa or more, and a tensile strength of 380 MPa or more.

The invention relates to a method for working a metal casting strand (17) that is round in cross-section, by means of a reduction in cross-section in the final solidification region with the aid of at least three forming tools which are distributed around the circumference and act simultaneously on the casting strand (17). In order to provide advantageous working conditions, according to the invention the casting strand (17) is formed by forging tools (2, 3) constituting the forming tools in a longitudinal portion for each forming stroke, which portion corresponds to at least a fourth of the strand diameter before the reduction in cross-section, and the forging tools (2, 3) are rotated by an angle step about the axis of the casting strand (17) between the forming strokes.

A preparation method of glassless grain-oriented silicon steel includes the following operations. During a decarburization annealing, a thickness of an oxide film on a surface of strip is 1.5-2.5 μm; an atomic weight ratio of Si element and Fe element in the oxide film satisfies: Si/(Si+Fe)≥0.76; during a high-temperature annealing, a cooling stage includes sequentially: cooling with an inner cover when a temperature drops from 1200° C. to 500° C.; wherein a protective gas is a mixed gas containing nitrogen and hydrogen, and a volume percentage of the hydrogen in the mixed gas is >3%; cooling with the inner cover when the temperature drops from 500° C. to 200° C.; wherein the protective gas is nitrogen; and cooling in air by removing the inner cover when the temperature is <200° C.

The present invention relates to a high manganese steel for low temperature applications and a method for manufacturing the same. The high manganese steel contains 0.3 wt % to 0.8 wt % of C, 18 wt % to 26 wt % of Mn, 0.01 wt % to 1 wt % of Si, 0.01 wt % to 0.5 wt % of Al, 0.1 wt % or less of Ti (excluding 0%), 1 wt % to 4.5 wt % of Cr, 0.1 wt % to 0.9 wt % of Cu, 0.03 wt % or less of S (excluding 0%), 0.3 wt % or less of P (excluding 0%), 0.001 wt % to 0.03 wt % of N, 0.004 wt % or less of B (excluding 0%), and a remainder of Fe and other inevitable impurities, wherein a microstructure comprises an austenite single phase structure, and an average grain size of the austenite is 50 μm or less.