A method for manufacturing thin-specification high-Ti wear-resistant steel NM450 comprises the steps of preparing melted iron in a blast-furnace, preprocessing the melted iron, smelting the melted iron in a converter, refining the melted steel in a LF furnace, refining the melted steel in a RH furnace, conventional slab continuous casting, heating the slab in a heating furnace, dephosphorizing the slab by high-pressure water, heating the slab in a hot continuous rolling mill, performing ultra fast cooling, reeling, flattening, heating, quenching, tempering and finishing.

The present invention relates to a steel for a mold, including 0.070C0.130 mass %, 0.01Si0.60 mass %, 0.02Mn0.60 mass %, 0.003P0.150 mass %, 0.005Cu1.50 mass %, 0.005Ni0.80 mass %, 7.50Cr8.40 mass %, 0.70Mo1.20 mass %, 0.01V0.30 mass %, 0.010Al0.120 mass %, and 0.015N0.095 mass %, with the balance being Fe and unavoidable impurities. The steel for a mold according to the present invention satisfies all of 6 properties of SA property, tempering hardness, residual stress, machinability, impact value and corrosion resistance.

Provided is a plated, ultra-low carbon steel sheet which has excellent strength, formability, and surface properties to allow for the weight lightness of automobiles and a manufacturing method therefor and, more specifically, to a galvanized steel sheet and a manufacturing method therefor, wherein the galvanized steel sheet has high strength and high formability and as such, can be suitably used as a material for an automobile outer body.

A flat steel product for production of a sheet metal component by hot forming includes a steel substrate consisting of a steel including 0.1-3% by weight of Mn and optionally up to 0.01% by weight of B, an aluminium-based coating disposed on at least one side of the steel substrate. A coating here has an applied layer weight of 15-30 g/m.sup.2. In addition, the coating has an Al base layer consisting of 1.0-15% by weight of Si, optionally 2-4% by weight of Fe, 0.1-5.0% by weight of alkali metals or alkaline earth metals, and optional further constituents, the contents of which are limited to a total of not more than 2.0% by weight, and aluminium as the balance.

A flat steel product for production of a sheet metal component by hot forming includes a steel substrate consisting of a steel including 0.1-3% by weight of Mn and optionally up to 0.01% by weight of B, an aluminium-based coating disposed on at least one side of the steel substrate. A coating here has an applied layer weight of 15-30 g/m.sup.2. In addition, the coating has an Al base layer consisting of 1.0-15% by weight of Si, optionally 2-4% by weight of Fe, 0.1-5.0% by weight of alkali metals or alkaline earth metals, and optional further constituents, the contents of which are limited to a total of not more than 2.0% by weight, and aluminium as the balance.

To provide a galvanized steel sheet having high strength, specifically, a tensile strength of 1,150 MPa or more, and excellent resistance spot weldability, a base steel sheet has a defined chemical composition, an amount of diffusible hydrogen in the base steel sheet is 0.20 mass ppm or less, and surface roughness Ra of the galvanized steel sheet is 0.6 ?m or less.

The invention relates to a method for producing a flat steel product made of a medium manganese steel having a TRIP/TWIP effect. The aim of the invention is to achieve an improvement in the yield strength when a sufficient residual deformability of the produced flat steel product is obtained. This aim is achieved by the following steps: cold rolling a hot or cold strip, annealing the cold-rolled hot or cold strip at 500 to 840 C. for 1 minute to 24 hours, temper rolling or finishing the annealed hot or cold strip to form a flat steel product having a degree of deformability between 0.3% and 60%. The invention further relates to a flat steel product produced according to said method and to a use thereof.

A chassis component for a motor vehicle is disclosed. The chassis component (1) is manufactured at least partially from a multi-layer steel sheet (10, 20, 30). The multi-layer steel sheet (10, 20, 30) includes at least three steel layers, including two outer steel layers (11, 12; 21, 22; 31, 32) and one inner steel layer (13, 23, 33). At least one outer steel layer (11, 12; 21, 22; 31, 32) of the multi-layer steel sheet (10, 20, 30) has a tensile strength of at least 1200 MPa. A method for producing a chassis component for a motor vehicle, in particular a wheel (1) or a part thereof, is also disclosed.

The present disclosure relates to a method for producing a semifinished product with modified surface, comprising at least one method step of at least regionally modifying the surface of a coated, skin-pass-rolled, oiled, cleaned metallic steel substrate via low-pressure or atmospheric-pressure plasma treatment of said surface regions with oxygen, argon or a mixture of oxygen and argon as process gas. The present disclosure further relates to the accordingly produced semifinished products and/or flat steel products, optionally formed semifinished products and/or flat steel products, and also to their use.

The present invention relates to: a steel material for hot forming, used for a vehicle and the like; a hot-formed member; and a method for manufacturing same. In the method, when the formed steel material is skin pass rolled, rolling pressure and roughness of skin pass rolling rolls are controlled so that bendability can be improved.