Arcelormittal Inactive USPTO patents

A hot rolled and heat-treated steel sheet, made of a steel having a composition including, by weight percent: C: 0.03-0.18%, Mn: 6.0-11.0%, Mo: 0.05-0.5%, B: 0.0005-0.005%, S≤0.010%, P≤0.020%, N≤0.008%, and including optionally one or more of the following elements, in weight percentage: Al<3%, Si≤1.20%, Ti≤0.050%, Nb=0.050%, Cr≤0.5%, V≤0.2%, the remainder of the composition being iron and unavoidable impurities resulting from the smelting, the steel sheet having a microstructure including, in surface fraction, from 10% to 60% of retained austenite, from 40% to 90% of ferrite, less than 5% of martensite, carbides below 0.8%, and an inhomogeneous repartition of manganese, characterized by a manganese distribution with a slope above or equal to −40.

A cold rolled, annealed and tempered steel sheet, made of a steel having a composition including, by weight percent: C: 0.03-0.18%, Mn: 6.0-11.0%, Al: <3%, Mo: 0.05-0.5%, B: 0.0005-0.005%, S≤0.010%, P≤0.020%, N≤0.008%, and optionally one or more of the following elements, in weight percentage: Si≤1.20%, Ti≤0.050%, Nb≤0.050%, Cr≤0.5%, V≤0.2%, the remainder of the composition being iron and unavoidable impurities resulting from the smelting, the steel sheet having a microstructure including, in surface fraction, from 0% to 30% of ferrite, such ferrite having a grain size below 1.0 μm, from 3% to 30% of retained austenite, from 40 to 95% of tempered martensite less than 5% of fresh martensite, a carbon [C]A and manganese [Mn]A content in austenite, expressed in weight percent, such that the ratio ([C]A2×[Mn]A)/(C %2×Mn %) is below 7.80, C % and Mn % being the nominal values in carbon and manganese in weight %.

Equipment for the continuous hot dip-coating of a metal strip 9 including an annealing furnace, a tank 2 containing a liquid metal bath 3, a snout connecting the annealing furnace and tank 2, through which the metal strip 9 runs in a protective atmosphere and the lower part of the snout, the sabot 5, is at least partly immersed in the liquid metal bath 3 in order to define with the surface of the bath, and inside this snout, a liquid seal 6, an overflow 7 not connected to the snout, the overflow 7 including at least one tray 8, placed in the vicinity of the strip 9 when entering the liquid metal bath 3 and encompassed by liquid seal 6.

An assembly of an aluminum-based part and a press hardened steel part provided with an alloyed coating including in weight percent, 0.1 to 15.0% silicon, 15.0 to 70% of iron, 0.1 to 20.0% of zinc, 0.1 to 4.0% of magnesium, the balance being aluminum, on at least one of the surfaces thereof placed so as to be in contact with the aluminum-based part.

A cold rolled and annealed steel sheet, made of a steel having a composition including, by weight percent: C: 0.03-0.18%, Mn: 6.0-11.0%, Al: 0.2-3%, Mo: 0.05-0.5%, B: 0.0005-0.005%, S 0.010%, P 0.020%, N 0.008%, and including optionally one or more of the following elements, in weight percentage: Si≤1.20%, Ti≤0.050%, Nb≤0.050%, Cr≤0.5%, V≤0.2%, the remainder of the composition being iron and unavoidable impurities resulting from the smelting, the steel sheet having a microstructure including, in surface fraction, from 25% to 55% of retained austenite, from 45% to 75% of ferrite, less than 5% of fresh martensite, a carbon [C]A and manganese [Mn]A content in austenite, expressed in weight percent, such that the ratio ([C]A×[Mn]2A)/(C %×Mn %) is from 19.0 to 41.0 wt %, C % and Mn % being the nominal values in carbon and manganese in weight % and a carbides density below 3×106/mm2 and—an inhomogeneous repartition of manganese characterized by a manganese distribution with a slope above or equal to −30.

Rear lower control arm (5) for a motor vehicle including a top part (5t) and a bottom part (5b) defining together a hollow volume (5h), the top and bottom parts (5t, 5b) each including respectively a top and bottom first hole (17t, 17b) and a top and bottom second hole (19t, 19b), wherein the top and bottom parts (5t, 5b) are joined together by securing together at least part of said top and bottom horizontal surface outer peripheries (5tho, 5bho), at least part of the top and bottom first hole side walls outer peripheries (17tso, 17bso), at least part of said top and bottom second hole side walls outer peripheries (19tso, 19bso).

A method for producing a zinc or zinc-alloy coated steel sheet with a tensile strength higher than 900 MPa, for the fabrication of resistance spot welds containing in average not more than two Liquid Metal Embrittlement cracks per weld having a depth of 100 μm or more, with steps of providing a cold-rolled steel sheet, heating cold-rolled steel sheet up to a temperature T1 between 550° C. and Ac1+50° C. in a furnace zone with an atmosphere (A1) containing from 2 to 15% hydrogen by volume, so that the iron is not oxidized, then adding in the furnace atmosphere, water steam or oxygen with an injection flow rate Q higher than (0.07%/h×α), α being equal to 1 if said element is water steam or equal to 0.52 if said element is oxygen, at a temperature T≥T1, so to obtain an atmosphere (A2) with a dew point DP2 between −15° C. and the temperature Te of the iron/iron oxide equilibrium dew point, then heating the sheet from temperature T1 up to a temperature T2 between 720° C. and 1000° C. in a furnace zone under an atmosphere (A2) of nitrogen containing from 2 to 15% hydrogen and more than 0.1% CO by volume, with an oxygen partial pressure higher than 10−21 atm., wherein the duration to of heating of the sheet from temperature T1 up to the end of soaking at temperature T2 is between 100 and 500 s, soaking the sheet at T2, then cooling the sheet at a rate between 10 and 400° C./s, then coating the sheet with zinc or zinc-alloy coating.

A method of casting a steel semi-product from a liquid steel, the steel semi-product having a targeted composition in titanium of at least 3.5% in weight.

A cold rolled, coated and post batch annealed steel sheet produced by a method is provided.

The present invention relates to a manufacturing method of a steel strip, a steel strip with controlled decarburized depth, a spot welded joint and the use of said steel strip or said spot welded joint.

A section mill (10) for the rolling of steel sections is disclosed.

A steel sheet has a composition comprising, by weight: 0.010%≤C≤0.080%, 0.06%≤Mn≤3%, Si≤1.5%, 0.005%≤Al≤1.5%, S≤0.030%, P≤0.040%, Ti and B such that: 3.2%≤Ti≤7.5% and (0.45×Ti)−1.35≤B≤(0.45×Ti)−0.43, optionally Ni≤1%, Mo≤1%, Cr≤3%, Nb≤0.1%, V≤0.1%, the remainder being iron and unavoidable impurities resulting from the smelting.

A press hardened coated steel part with high resistance to delayed fracture, the coating containing (Fex—Aly) intermetallic compounds resulting from the diffusion of iron into an aluminum or an aluminum-based alloy, or an aluminum alloy of a precoating, wherein the chemical composition of the steel includes, in weight: 0.16%≤C≤0.42%, 0.1%≤Mn≤3%, 0.07%≤Si≤1.60%, 0.002%≤Al≤0.070%, 0.02%≤Cr≤1.0%, 0.0005≤B≤0.005%, 0.002%≤Mg≤0.007%, 0.002%≤Ti≤0.11%, 0.0008%≤O≤0.005%, wherein (Ti)×(O)2×107≤2, 0.001%≤N≤0.007%, 0.001%≤S≤0.005%, 0.001%≤P≤0.025% and optionally one or more elements selected from the list of: 0.005%≤Ni≤0.23%, 0.005%≤Nb≤0.060%, the remainder being Fe and unavoidable impurities, and wherein the microstructure includes at least 95% martensite.

A method is for producing a high strength coated steel sheet having an improved ductility and an improved formability, and a chemical composition containing: 0.13%≤C≤0.22%, 1.9%≤Si≤2.3%, 2.4%≤Mn≤3%, Al≤0.5%, Ti≤0.05%, Nb≤0.05%, the remainder being Fe and unavoidable impurities.

The present invention relates to a method for the manufacture of a galvannealed steel sheet including the steps of A.) coating of the steel sheet with a first coating consisting of nickel and having a thickness between 150 nm and 650 nm, the steel sheet having the following composition in weight percentage 0.10<C<0.40%, 1.5<Mn<3.0%, 0.7<Si<3.0%, 0.05<Al<1.0%, 0.75<(Si+Al)<3.0%, and on a purely optional basis, one or more elements such as Nb≤0.5%, B≤0.010%, Cr s 1.0%, Mo≤0.50%, Ni≤1.0%, Ti≤0.5%., the remainder of the composition is made up of iron and inevitable impurities resulting from the elaboration, B.) annealing of the coated steel sheet being annealed at a temperature between 600 to 1200° C., C.) coating of the steel sheet obtained in step B.) with a second coating based on zinc and D.) an alloying heat treatment to form a galvannealed steel sheet.

A cold rolled and heat-treated steel sheet, the steel including, in weight percentage, 0.17%≤carbon≤0.25%, 2%≤manganese≤3%, 0.9%≤silicon≤2%, 0%≤aluminum≤0.09%, 0.01%≤molybdenum≤0.2%, 0%≤phosphorus≤0.02%, 0%≤sulfur≤0.03%, 0%≤nitrogen≤0.09%, and optionally one or more of the following elements 0%≤chromium≤0.3%, 0%≤niobium≤0.06%, 0%≤titanium≤0.06%, 0%≤vanadium≤0.1%, 0%≤calcium≤0.005%, 0%≤boron≤0.010%, 0%≤Magnesium≤0.05%, 0%≤Zirconium≤0.05%, 0%≤Cerium≤0.1%, and the balance including iron and unavoidable impurities, the steel sheet having a microstructure of—50% to 80% of Bainite, 10% to 30% of residual austenite, 15% to 50% of Partitioned martensite, 0% to 10% of ferrite and 0% to 5% fresh martensite in area fractions, and a ferrite-enriched layer extending up to 50 microns from both surfaces of the steel sheet, such ferrite-enriched layer having a mean ferrite content from 55% to 80% in area fraction.