Patent classifications
C21D9/52
High-Hardness Steel Product and Method of Manufacturing the Same
Described is a hot-rolled steel strip product including a composition consisting of, in terms of weight percentages, 0.14% to 0.35% C, 0% to 0.5% Si, 0.05% to 0.40% Mn, 0.1% or less Al, 0.1% to 0.4% Cu, 0.2% to 0.9% Ni, 0.2% to 0.9% Cr, 0.2% or less Mo, 0.005% or less Nb, 0.035% or less Ti, 0.05% or less V, 0.0005% to 0.0050% B, 0.025% or less P, 0.008% or less S, 0.01% or less N, 0.01% or less Ca, and the remainder being Fe and inevitable impurities, wherein the steel product has a Brinell hardness in the range of 420 to 580 HBW.
METHOD FOR MANUFACTURING OF STAINLESS STEEL STRIPS
The invention relates to a method for manufacturing strips of stainless steel, comprising hot rolling in an initial process (A) and subsequently cold rolling in a cold rolling line (B). The hot rolling is stopped when the strip thickness has been reduced to a thickness between 2.0 mm and 6.5 mm. The subsequent cold rolling is passed at least one time through said cold rolling line, which comprises in the following order: At least one cold rolling mill (11-13) in the initial part of the line, at least one annealing section (17), a scale breaking step (21), a shot blasting step (23) and at least one pickling section (26, 27) utilizing a mixture of nitric acid HNO.sub.3, hydrofluoric acid HF and optionally sulphuric acid H.sub.2SO.sub.4.
METHOD FOR MANUFACTURING OF STAINLESS STEEL STRIPS
The invention relates to a method for manufacturing strips of stainless steel, comprising hot rolling in an initial process (A) and subsequently cold rolling in a cold rolling line (B). The hot rolling is stopped when the strip thickness has been reduced to a thickness between 2.0 mm and 6.5 mm. The subsequent cold rolling is passed at least one time through said cold rolling line, which comprises in the following order: At least one cold rolling mill (11-13) in the initial part of the line, at least one annealing section (17), a scale breaking step (21), a shot blasting step (23) and at least one pickling section (26, 27) utilizing a mixture of nitric acid HNO.sub.3, hydrofluoric acid HF and optionally sulphuric acid H.sub.2SO.sub.4.
Apparatus and method for rapidly heating cold-rolled strip steel
An apparatus and a method for rapidly heating cold-rolled strip steel (10). The apparatus for rapidly heating cold-rolled strip steel (10) comprises a heating zone, a soaking zone, and a cooling zone, and the heating zone is sequentially divided into a first heating section (1), a second heating section (2), a third heating section (3), and a fourth heating section (4) along a moving direction of the strip steel (10) to be heated, the first heating section (1) and the fourth heating section (4) being radiant heating sections, and the second heating section (2) and the third heating section (3) being inductive heating sections. The method for rapidly heating cold-rolled strip steel (10) uses the apparatus for rapidly heating cold-rolled strip steel (10) to heat the strip steel (10).
Apparatus and method for rapidly heating cold-rolled strip steel
An apparatus and a method for rapidly heating cold-rolled strip steel (10). The apparatus for rapidly heating cold-rolled strip steel (10) comprises a heating zone, a soaking zone, and a cooling zone, and the heating zone is sequentially divided into a first heating section (1), a second heating section (2), a third heating section (3), and a fourth heating section (4) along a moving direction of the strip steel (10) to be heated, the first heating section (1) and the fourth heating section (4) being radiant heating sections, and the second heating section (2) and the third heating section (3) being inductive heating sections. The method for rapidly heating cold-rolled strip steel (10) uses the apparatus for rapidly heating cold-rolled strip steel (10) to heat the strip steel (10).
METHOD FOR PRODUCING A STEEL STRIP WITH IMPROVED BONDING OF METALLIC HOT-DIP COATINGS
A cold- or hot-rolled steel strip with a metallic coating, the steel strip having iron as the main constituent and, in addition to carbon, an Mn content of 8.1 to 25.0 wt. % and optionally one or more of the alloying elements Al, Si, Cr, B, Ti, V, Nb and/or Mo. The uncoated steel strip is first cleaned, a layer of pure iron is applied to the cleaned surface, an oxygen-containing, iron-based layer containing more than five mass percent of oxygen is applied to the layer of pure iron. The steel strip is then annealed and is reduction-treated in a reducing furnace atmosphere during the annealing treatment to obtain a surface consisting mainly of metallic iron. The steel strip is then hot-dip coated with the metallic coating. This creates uniform and reproducible bonding conditions for the coating on the steel strip surface.
METHOD FOR PRODUCING A STEEL STRIP WITH IMPROVED BONDING OF METALLIC HOT-DIP COATINGS
A cold- or hot-rolled steel strip with a metallic coating, the steel strip having iron as the main constituent and, in addition to carbon, an Mn content of 8.1 to 25.0 wt. % and optionally one or more of the alloying elements Al, Si, Cr, B, Ti, V, Nb and/or Mo. The uncoated steel strip is first cleaned, a layer of pure iron is applied to the cleaned surface, an oxygen-containing, iron-based layer containing more than five mass percent of oxygen is applied to the layer of pure iron. The steel strip is then annealed and is reduction-treated in a reducing furnace atmosphere during the annealing treatment to obtain a surface consisting mainly of metallic iron. The steel strip is then hot-dip coated with the metallic coating. This creates uniform and reproducible bonding conditions for the coating on the steel strip surface.
Bainitic steel of high strength and high elongation and method to manufacture said bainitic steel
The invention relates to a bainite steel consisting of the following elements in weight %: C: 0.25-0.55 Si: 0.5-1.8 Mn: 0.8-3.8 Cr: 0.2-2.0 Ti: 0.0-0.1 Cu: 0.0-1.2 V: 0.0-0.5 Nb: 0.0-0.06 Al: 0.0-2.75 N: <0.004 P: <0.025 S: <0.025 and a method for manufacturing a bainite steel strip that comprises the step of cooling the coiled strip of such composition to ambient temperature, during which the bainite transformation takes place.
Bainitic steel of high strength and high elongation and method to manufacture said bainitic steel
The invention relates to a bainite steel consisting of the following elements in weight %: C: 0.25-0.55 Si: 0.5-1.8 Mn: 0.8-3.8 Cr: 0.2-2.0 Ti: 0.0-0.1 Cu: 0.0-1.2 V: 0.0-0.5 Nb: 0.0-0.06 Al: 0.0-2.75 N: <0.004 P: <0.025 S: <0.025 and a method for manufacturing a bainite steel strip that comprises the step of cooling the coiled strip of such composition to ambient temperature, during which the bainite transformation takes place.
IRON-MANGANESE ALLOY HAVING IMPROVED WELDABILITY
Disclosed is an iron-manganese alloy including, by weight: 25.0%≤Mn≤32.0%; 7.0%≤Cr≤14.0%; 0≤Ni≤2.5%; 0.05%≤N≤0.30%; 0.1≤Si≤0.5%; and optionally 0.010%≤rare earths≤0.14%. The remainder being iron and residual elements resulting from manufacturing.