WO2012153012A1 - Procede de fabrication d'acier martensitique a tres haute resistance et tôle ou piece ainsi obtenue - Google Patents
Procede de fabrication d'acier martensitique a tres haute resistance et tôle ou piece ainsi obtenue Download PDFInfo
- Publication number
- WO2012153012A1 WO2012153012A1 PCT/FR2012/000153 FR2012000153W WO2012153012A1 WO 2012153012 A1 WO2012153012 A1 WO 2012153012A1 FR 2012000153 W FR2012000153 W FR 2012000153W WO 2012153012 A1 WO2012153012 A1 WO 2012153012A1
- Authority
- WO
- WIPO (PCT)
- Prior art keywords
- steel
- sheet
- temperature
- average
- blank
- Prior art date
Links
Classifications
-
- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22C—ALLOYS
- C22C38/00—Ferrous alloys, e.g. steel alloys
- C22C38/18—Ferrous alloys, e.g. steel alloys containing chromium
- C22C38/38—Ferrous alloys, e.g. steel alloys containing chromium with more than 1.5% by weight of manganese
-
- C—CHEMISTRY; METALLURGY
- C21—METALLURGY OF IRON
- C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
- C21D1/00—General methods or devices for heat treatment, e.g. annealing, hardening, quenching or tempering
- C21D1/18—Hardening; Quenching with or without subsequent tempering
- C21D1/19—Hardening; Quenching with or without subsequent tempering by interrupted quenching
-
- C—CHEMISTRY; METALLURGY
- C21—METALLURGY OF IRON
- C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
- C21D1/00—General methods or devices for heat treatment, e.g. annealing, hardening, quenching or tempering
- C21D1/62—Quenching devices
- C21D1/673—Quenching devices for die quenching
-
- C—CHEMISTRY; METALLURGY
- C21—METALLURGY OF IRON
- C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
- C21D7/00—Modifying the physical properties of iron or steel by deformation
- C21D7/13—Modifying the physical properties of iron or steel by deformation by hot working
-
- C—CHEMISTRY; METALLURGY
- C21—METALLURGY OF IRON
- C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
- C21D8/00—Modifying the physical properties by deformation combined with, or followed by, heat treatment
- C21D8/02—Modifying the physical properties by deformation combined with, or followed by, heat treatment during manufacturing of plates or strips
-
- C—CHEMISTRY; METALLURGY
- C21—METALLURGY OF IRON
- C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
- C21D8/00—Modifying the physical properties by deformation combined with, or followed by, heat treatment
- C21D8/02—Modifying the physical properties by deformation combined with, or followed by, heat treatment during manufacturing of plates or strips
- C21D8/0221—Modifying the physical properties by deformation combined with, or followed by, heat treatment during manufacturing of plates or strips characterised by the working steps
- C21D8/0226—Hot rolling
-
- C—CHEMISTRY; METALLURGY
- C21—METALLURGY OF IRON
- C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
- C21D8/00—Modifying the physical properties by deformation combined with, or followed by, heat treatment
- C21D8/02—Modifying the physical properties by deformation combined with, or followed by, heat treatment during manufacturing of plates or strips
- C21D8/0221—Modifying the physical properties by deformation combined with, or followed by, heat treatment during manufacturing of plates or strips characterised by the working steps
- C21D8/0231—Warm rolling
-
- C—CHEMISTRY; METALLURGY
- C21—METALLURGY OF IRON
- C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
- C21D8/00—Modifying the physical properties by deformation combined with, or followed by, heat treatment
- C21D8/02—Modifying the physical properties by deformation combined with, or followed by, heat treatment during manufacturing of plates or strips
- C21D8/0247—Modifying the physical properties by deformation combined with, or followed by, heat treatment during manufacturing of plates or strips characterised by the heat treatment
- C21D8/0263—Modifying the physical properties by deformation combined with, or followed by, heat treatment during manufacturing of plates or strips characterised by the heat treatment following hot rolling
-
- C—CHEMISTRY; METALLURGY
- C21—METALLURGY OF IRON
- C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
- C21D9/00—Heat treatment, e.g. annealing, hardening, quenching or tempering, adapted for particular articles; Furnaces therefor
- C21D9/46—Heat treatment, e.g. annealing, hardening, quenching or tempering, adapted for particular articles; Furnaces therefor for sheet metals
-
- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22C—ALLOYS
- C22C38/00—Ferrous alloys, e.g. steel alloys
- C22C38/02—Ferrous alloys, e.g. steel alloys containing silicon
-
- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22C—ALLOYS
- C22C38/00—Ferrous alloys, e.g. steel alloys
- C22C38/04—Ferrous alloys, e.g. steel alloys containing manganese
-
- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22C—ALLOYS
- C22C38/00—Ferrous alloys, e.g. steel alloys
- C22C38/06—Ferrous alloys, e.g. steel alloys containing aluminium
-
- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22C—ALLOYS
- C22C38/00—Ferrous alloys, e.g. steel alloys
- C22C38/18—Ferrous alloys, e.g. steel alloys containing chromium
-
- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22C—ALLOYS
- C22C38/00—Ferrous alloys, e.g. steel alloys
- C22C38/18—Ferrous alloys, e.g. steel alloys containing chromium
- C22C38/22—Ferrous alloys, e.g. steel alloys containing chromium with molybdenum or tungsten
-
- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22C—ALLOYS
- C22C38/00—Ferrous alloys, e.g. steel alloys
- C22C38/18—Ferrous alloys, e.g. steel alloys containing chromium
- C22C38/34—Ferrous alloys, e.g. steel alloys containing chromium with more than 1.5% by weight of silicon
-
- C—CHEMISTRY; METALLURGY
- C21—METALLURGY OF IRON
- C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
- C21D2211/00—Microstructure comprising significant phases
- C21D2211/008—Martensite
Definitions
- the invention relates to a process for the manufacture of sheets or parts made of steel with a martensitic structure, with a mechanical strength greater than that which could be obtained by austenitization, and then to a method for manufacturing steel sheets or parts made of steel with a martensitic structure.
- simple fast cooling treatment with martensitic quenching, and strength and elongation properties for their application to the manufacture of energy absorbing parts in motor vehicles.
- it is sought to produce steel parts combining high mechanical strength, high impact resistance and good corrosion resistance.
- This type of combination is particularly desirable in the automotive industry where significant vehicle lightening is sought. This can be achieved particularly through the use of steel parts with very high mechanical properties whose microstructure is martensitic or bainito-martensitic.
- Anti-intrusion parts, structure or participating in the safety of motor vehicles such as: bumper cross members, door or center pusher reinforcements, wheel arms, require for example the qualities mentioned above.
- Their thickness is preferably less than 3 millimeters.
- the patent EP0971044 thus discloses the manufacture of a steel sheet coated with aluminum or an aluminum alloy, the composition of which comprises in weight content: 0.15-0.5% C, 0.5- 3% Mn, 0.1-0.5% Si, 0.011% Cr, Ti ⁇ 0.2%, Al ⁇ 0.1%, P ⁇ 0.1%, S ⁇ 0.05%, 0.0005% ⁇ B ⁇ 0.08%, the balance being iron and impurities inherent in the elaboration.
- This sheet is heated so as to obtain an austenitic transformation and hot stamped so as to produce a part, which is then cooled rapidly to obtain a martensitic or martensitobasitic structure. In this way, it is possible to obtain, for example, a mechanical strength greater than 1500 MPa. However, we seek to obtain parts with even greater mechanical strength. We search still, at a given level of mechanical strength, to reduce the carbon content of the steel so as to improve its weldability.
- GB 1, 166,042 discloses a steel composition adapted to this process of ausforming, which comprises 0.1-0.6% C, 0.25-5% Mn, 0.5-2% AI , 0.5-3% Mo, 0.01 -2% Si, 0.01-1% V.
- These steels include significant additions of molybdenum, manganese, aluminum, silicon and / or copper. These are intended to create a larger metastability domain for austenite, ie to delay the onset of the transformation from austenite to ferrite, bainite or perlite, at the temperature at which performs hot deformation.
- Most studies on ausforming have been conducted on steels with a carbon content greater than 0.3%.
- these compositions adapted to the ausforming have the disadvantage of requiring special precautions for welding, and also have particular difficulties in the case where it is desired to perform a metal coating quenching.
- these compositions have expensive addition elements.
- (C) denotes the carbon content of the steel, expressed as a percentage by weight.
- a method of manufacture is thus sought which makes it possible to obtain an ultimate tensile strength of 50 MPa for expression (1), ie a strength greater than 3220 (C ) + 958 MPa for this steel. It seeks to have a method for the manufacture of sheet with a very high yield strength, that is greater than 1300 MPa. It is also sought to have a method for the manufacture of sheets or parts usable directly, that is to say without the need for a tempering treatment after quenching. It is also sought to have a manufacturing process for the manufacture of a sheet or a readily coated part by dipping in a metal bath.
- the present invention aims to solve the problems mentioned above. It aims in particular to provide sheets with a yield strength greater than 1300 MPa, a mechanical strength expressed in megapascals greater than (3220 (C) +958) MPa, and preferably a total elongation greater than 3%.
- the subject of the invention is a method for manufacturing a sheet of steel with a totally martensitic structure having an average slat size of less than 1 micrometer, the average elongation factor of the slats being between 2 and 5 , it being understood that the elongation factor of a
- a semi-finished steel product whose composition comprises, the contents being expressed by weight, 0.15% ⁇ C ⁇ 0.40%, 1.5% ⁇ Mn ⁇ 3%, 0.005% ⁇ If ⁇ 2%, 0.005% ⁇ Al ⁇ 0.1%, 1, 8% ⁇ Cr ⁇ 4%, 0% ⁇ Mo ⁇ 2%, with 2.7% ⁇ 0.5 (Mn) + (Cr) +3 (Mo) ⁇ 5.7%, S ⁇ 0.05%, P ⁇ 0.1%, and optionally: 0% ⁇ Nb ⁇ 0.050%, 0.01% ⁇ Ti ⁇ 0.1 %, 0.0005% ⁇ B ⁇ 0.005%, 0.0005% ⁇ Ca ⁇ 0.005%, the remainder of the composition consisting of iron and unavoidable impurities resulting from the preparation,
- the half-product is heated to a temperature Ti of between 1050 ° C. and 1250 ° C., and then
- a rough rolling is carried out of the heated half-product at a temperature T 2 of between 1000 and 880 ° C., with a cumulative reduction rate ⁇ 3 of greater than 30% so as to obtain a sheet with a completely recrystallized austenitic structure; of average grain size less than 40 microns and preferably 5 microns, the cumulative reduction rate ⁇ 3 being defined by: Ln-,. e, a designating
- the sheet is cooled to a temperature T3 of between 600 ° C. and 400 ° C. in the austenitic metastable domain, at a speed VRI greater than 2 ° C./s, and then
- a finishing hot rolling is carried out at the temperature T 3 of the non-completely cooled sheet, with a cumulative reduction ratio b greater than 30% so as to obtain a sheet, the cumulative reduction ratio
- the sheet is cooled at a speed V R2 greater than the critical speed of martensitic quenching.
- the subject of the invention is also a process for manufacturing a piece of steel with a totally martensitic structure having an average slat size of less than 1 micrometer, the average elongation factor of slats being between 2 and 5, comprising the successive steps and in this order according to which:
- a steel blank whose composition comprises, the contents being expressed by weight, 0.15% ⁇ C ⁇ 0.40%, 1, 5% ⁇ Mn ⁇ 3%, 0.005% ⁇ Si ⁇ 2%, 0.005% ⁇ Al ⁇ 0.1%, 1, 8% ⁇ Cr ⁇ 4%, 0% ⁇ Mo ⁇ 2%, with 2.7% ⁇ 0.5 (Mn) + (Cr) +3 (Mo ) ⁇ 5.7%, S ⁇ 0.05%, P ⁇ 0.1%, optionally: 0% ⁇ Nb ⁇ 0.050%, 0.01% ⁇ Ti ⁇ 0.1%, 0.0005% ⁇ B ⁇ 0.005%, 0.0005% ⁇ Ca ⁇ 0.005%, the remainder of the composition consisting of iron and unavoidable impurities resulting from the preparation,
- the blank is heated to a temperature Ti between Ac 3 and Ac 3 + 250 ° C. so that the average austenitic grain size is less than 40 microns, and preferably 5 microns, and then
- the heated blank is transferred into a hot stamping press or a hot forming device, and then
- the blank is cooled to a temperature T3 of between 600 ° C. and 400 ° C., at a speed V R greater than 2 ° C./s in order to avoid a transformation of the austenite,
- the part is cooled to a speed V R2 greater than the critical speed of martensitic quenching.
- the blank is hot-stamped so as to obtain a workpiece, then the workpiece is held in the stamping tool so as to cool it at a speed V R2 greater than the critical speed of martensitic quenching. .
- the blank is pre-coated with aluminum or an aluminum-based alloy. According to another preferred embodiment, the blank is pre-coated with zinc or a zinc-based alloy.
- the sheet or piece of steel obtained by any one of the above manufacturing processes is subjected to a subsequent heat treatment of tempering at a temperature T 4 of between 150 and 600 ° C. for a period of time between 5 and 30 minutes.
- the subject of the invention is also an unreturned steel sheet having a yield strength greater than 1300 MPa, with a mechanical strength greater than (3220 (C) +958) megapascals, it being understood that (C) denotes the carbon content in weight percent of the steel, obtained according to any of the above manufacturing processes, of a totally martensitic structure, having an average slat size of less than 1 micrometer, the average elongation factor of slats being between 2 and 5
- the invention also relates to a piece of unreturned steel obtained by any one of the above part manufacturing processes, the part comprising at least one zone of totally martensitic structure having an average slat size of less than 1 micrometer, the average elongation factor of the slats being between 2 and 5, the yield strength in said zone being greater than 1300 MPa and the mechanical strength being greater than (3220 (C) +958) megapascals, it being understood that (C) refers to the percentage carbon content of the steel.
- the subject of the invention is also a sheet or a piece of steel obtained by the process with the above treatment of income, the steel having a totally martensitic structure, having in at least one zone an average slat size of less than 1 , 2 micrometer, the average elongation factor of the slats being between 2 and 5.
- FIG. 1 shows an example of microstructure of steel sheet manufactured by the method according to the invention.
- FIG. 2 shows an example of microstructure of the same steel manufactured by a reference method, by heating in the austenitic domain and then by simple martensitic quenching.
- FIG. 3 shows an exemplary piece of steel microstructure manufactured by the process according to the invention.
- the carbon content of the steel is less than 0.15% by weight, the quenchability of the steel is insufficient given the process used and it is not possible to obtain a totally martensitic structure.
- this content is greater than 0.40%, welded joints made from these sheets or these parts have insufficient toughness.
- the optimum carbon content for the implementation of the invention is between 0.16 and 0.28%.
- Manganese lowers the initial formation temperature of martensite and slows the decomposition of austenite. In order to obtain sufficient effects to allow the implementation of the ausforming, the manganese content must not be less than 1, 5%. Moreover, when the manganese content exceeds 3%, segregated zones are present in excessive quantity which is detrimental to the implementation of the invention. A preferred range for the implementation of the invention is 8 to 2.5% Mn.
- the silicon content must be greater than 0.005% so as to contribute to the deoxidation of the steel in the liquid phase.
- the silicon should not exceed 2% by weight due to the formation of surface oxides which significantly reduce the processability in processes involving a continuous passage of the steel sheet in a coating metal bath.
- Chromium and molybdenum are very effective in delaying the transformation of austenite and in separating the transformation domains Ferritic-pearlitic and bainitic, ferrito- pearlitic transformation occurring at temperatures above bainitic transformation. These transformation domains are in the form of two distinct "noses" in an isothermal transformation chart TTT (transformation-temperature-time) from the austenite, which allows the implementation of the method according to the invention.
- TTT transformation-temperature-time
- the chromium content of the steel must be between 1.8% and 4% by weight in order for its delay effect on the transformation of the austenite to be sufficient.
- the chromium content of the steel takes into account the content of other elements that increase the quenchability such as manganese and molybdenum: in fact, given the respective effects of manganese, chromium and molybdenum on the transformations from the austenite, a combined addition of these elements must be carried out respecting the following condition, the respectively noted quantities (Mn) (Cr) (Mo) being expressed in weight percentage: 2.7% ⁇ 0.5 (Mn) + (Cr) 3 (MB) ⁇ 5.7%.
- the molybdenum content must not exceed 2% because of its excessive cost.
- the aluminum content of the steel according to the invention is not less than 0.005% so as to obtain sufficient deoxidation of the steel in the liquid state.
- the aluminum content is greater than 0.1% by weight, casting problems may occur. It is also possible to form inclusions of alumina in too large quantities or sizes which play a detrimental role on toughness.
- the sulfur and phosphorus contents of the steel are respectively limited to 0.05 and 0.1% in order to avoid a reduction in the ductility or toughness of the parts or sheets produced according to the invention.
- the steel may optionally contain niobium and / or titanium, which makes it possible to refine further refinement of the grain. Due to the heat curing these additions confer, they must however be limited to 0.050% for niobium and between 0.01 and 0.1% for titanium so as not to increase the forces during hot rolling. .
- the steel can also contain boron: indeed, the significant deformation of the austenite can accelerate the conversion to ferrite on cooling, a phenomenon that should be avoided. Addition of boron in an amount of between 0.0005 and 0.005% by weight makes it possible to guard against early ferritic transformation.
- the steel can also contain calcium in an amount between 0.0005 and 0.005%: by combining with oxygen and sulfur, calcium prevents the formation of large inclusions, harmful for the ductility of the sheets or parts thus manufactured.
- the rest of the composition of the steel consists of iron and unavoidable impurities resulting from the elaboration.
- the sheets or steel parts manufactured according to the invention are characterized by a totally slab martensite structure of great fineness: due to the specific thermomechanical cycle and composition, the average size of the martensitic slats is less than 1 micrometer and their average elongation factor is between 2 and 5.
- These microstructural characteristics are determined for example by observing the microstructure by scanning electron microscopy using a field effect gun ("MEB-FEG” technique) at a magnification higher than 1200x, coupled to an EBSD detector ("Electron Backscatter Diffraction"). It is defined that two contiguous slats are distinct when their disorientation is greater than 5 degrees.
- the average slat size is defined by the intercepts method known per se: the mean size of the intercepted slats is evaluated by randomly defined lines with respect to the microstructure. The measurement is performed on at least 1000 martensitic slats in order to obtain a representative average value.
- the morphology of individualized slats is determined by image analysis using software known in themselves: the maximum dimension L max and minimum ⁇ mm is determined for each lath martensite and? Max elongation factor. In order to be statistically representative, this
- the method according to the invention makes it possible to manufacture either rolled sheets or hot-stamped or heat-formed parts. These two modes will be successively exposed.
- the process for manufacturing hot-rolled sheets according to the invention comprises the following steps:
- a semi-finished steel product the composition of which has been described above, is supplied.
- This semi-finished product may for example be in the form of slab from continuous casting, thin slab or ingot.
- a continuous casting slab has a thickness of about 200 mm, a thin slab a thickness of about 50-80 mm.
- This semi-finished product is heated to a temperature Ti of between 1050 ° C. and 1250 ° C.
- the temperature ⁇ is greater than A c3 , the total conversion temperature to austenite at heating.
- This reheating thus makes it possible to obtain a complete austenitization of the steel as well as the dissolution of any possible niobium carbonitrides in the semi-finished product.
- This reheating step also makes it possible to carry out the various subsequent hot rolling operations that will be presented: a roughing operation is carried out on the semi-finished product at a temperature T 2 of between 1000 and 880 ° C.
- ⁇ 3 The cumulative reduction rate of the various stages of rolling at roughing is noted ⁇ 3 . If e, a is the thickness of the semi-finished product prior to hot rough rolling and ef is the thickness of the sheet after this e
- the cumulative reduction ratio ⁇ 3 during rough rolling must be greater than 30%.
- the austenite obtained is completely recrystallized with an average grain size of less than 40 micrometers or even 5 micrometers when the deformation ⁇ 3 is greater than 200% and when the temperature T 2 is between 950 and 880 ° C. .
- the sheet is then not completely cooled, that is to say up to intermediate temperature T3, so as to avoid transformation of the austenite, at a speed V R greater than 2 ° C / s to a temperature T 3 of between 600 ° C and 400 ° C, temperature range in which Austenite is metastable, ie in a field where it should not be present under conditions of thermodynamic equilibrium.
- Finishing is then carried out at the temperature T 3> the cumulative reduction ratio b being greater than 30%. Under these conditions, a plastically deformed austenitic structure is obtained in which recrystallization does not occur.
- the sheet is then cooled at a speed VR 2 greater than the critical martensitic quenching speed.
- the invention is not limited to this geometry and to this type of products, and can be implemented for the manufacture of long products, bars, profiles, by successive stages of hot deformation.
- a steel blank whose composition contains by weight: 0.15% ⁇ C ⁇ 0.40%, 1.5% ⁇ Mn ⁇ 3%, 0.005% ⁇ Si ⁇ 2%, 0.005% ⁇ Al ⁇ 0, 1%, 1, 8% ⁇ Cr ⁇ 4%, 0% ⁇ Mo ⁇ 2%, with 2.7% ⁇ 0.5 (Mn) + (Cr) +3 (Mo) ⁇ 5 , 7%, S ⁇ 0.05%, P ⁇ 0.1%, and optionally: 0% ⁇ Nb ⁇ 0.050%, 0.01% ⁇ Ti ⁇ 0.1%, 0.0005% ⁇ B ⁇ 0.005% , 0.0005% ⁇ Ca ⁇ 0.005%.
- This flat blank is obtained by cutting a sheet or a coil in a form related to the final geometry of the target part.
- This blank may be uncoated or optionally pre-coated.
- the pre-coating may be aluminum or an aluminum-based alloy.
- the sheet may advantageously be obtained by continuously dipping in a bath of aluminum-silicon alloy comprising by weight 5-1 1% silicon, 2 to 4% iron, optionally between 5 and 30 ppm of calcium, the rest being aluminum and unavoidable impurities resulting from the elaboration.
- the blank may also be pre-coated with zinc or a zinc-based alloy.
- the pre-coating can be in particular of the type galvanized with continuous dipping (“Gl”) or galvanized-alloyed (“GA”)
- the blank is heated to a temperature ⁇ between A c3 and A C 3 + 250 ° C.
- the heating is preferably carried out in an oven under ordinary atmosphere; during this step, an alloying between the steel and the precoat is observed.
- the alloyed coating protects the underlying steel from oxidation and decarburization and is suitable for subsequent hot deformation.
- the blank is held at temperature ⁇ to ensure the homogeneity of the temperature within it. Depending on the thickness of the blank, for example from 0.5 to 3 mm, the holding time at the temperature ⁇ varies from 30 seconds to 5 minutes.
- the steel structure of the blank is completely austenitic.
- the limitation of the temperature to A C 3 + 250 ° C has the effect of restricting the magnification of the austenitic grain to an average size of less than 40 micrometers.
- the average grain size is preferably less than 5 micrometers.
- the blank thus heated is transferred into a hot stamping press or into a hot forming device: the latter may for example be a "roll-forming" device in which the The blank is progressively deformed by hot forming into a series of rolls until the final geometry of the desired part is reached.
- the transfer of the blank to the press or to the shaping device must be carried out quickly enough not to cause transformation of the austenite.
- the blank is then cooled at a speed VRI greater than 2 ° C./s in order to avoid the transformation of the austenite, to a temperature T3 of between 600 ° C. and 400 ° C., a temperature range in which the Austenite is metastable.
- the stamping press or hot forming device it is also possible to reverse the order of these last two steps, ie to first cool the blank with a speed VRI greater than 2 ° C./s, and then to transfer this blank to stamping press or hot forming device, so that it can be stamped or shaped hot as follows.
- the blank is stamped or shaped at a temperature T3 of between 400 and 600 ° C., this hot deformation can be carried out in a single step or in several successive steps, as in the case of the roll-forming mentioned above. -above.
- the stamping starts it possible to obtain a part whose shape is not developable.
- the cumulative deformation s c must be greater than 30% so as to obtain a deformed non-recrystallized austenite.
- ⁇ the equivalent deformation defined in each point of the piece by and ⁇ 2 are the
- the hot forming mode is chosen such that the condition sc > 30% is satisfied at any point in the part formed.
- the part After hot deformation, the part is cooled at a speed V 2 greater than the critical speed of martensitic quenching so as to obtain a totally martensitic structure.
- this cooling can be achieved by holding the piece in the tooling with close contact with it.
- This cooling by thermal conduction can be accelerated by cooling the stamping tool, for example through channels machined in the tool for the circulation of a refrigerant.
- the hot stamping process of the invention therefore differs from the usual method of starting hot stamping as soon as the blank has been positioned in the press.
- the flow limit of the steel is the lowest at high temperature and the forces required by the press are the lowest.
- the method according to the invention consists in observing a waiting time so that the blank reaches a temperature range suitable for the ausforming, then hot stamping the blank at a significantly lower temperature than in the usual process.
- the stamping force required by the press is slightly higher but the final structure obtained thinner than in the usual process leads to greater mechanical properties of yield strength, strength and stability. ductility. To meet a specification corresponding to a given level of stress, it is therefore possible to reduce the thickness of the blanks and thereby reduce the stamping force of the parts according to the invention.
- the hot deformation immediately after stamping must be limited, this high temperature deformation tending to favor the formation of ferrite in the most deformed areas, which is sought to avoid.
- the method according to the invention does not include this limitation.
- the sheets or the steel parts may be used as such or subjected to a heat treatment of tempering, carried out at a temperature T 4 of between 150 and 600 ° C. for a period of time. between 5 and 30 minutes.
- This treatment of income has the effect of increasing the ductility at the price of a decrease in yield strength and strength.
- the inventors have however demonstrated that the method according to the invention, which gives a tensile strength Rm of at least 50 MPa higher than that obtained after conventional quenching, retained this advantage, even after tempering with temperatures ranging from 150 to 600 ° C.
- the fineness characteristics of the microstructure are preserved by this treatment of income, the average size of slats being less than 1, 2 micrometer, the average elongation factor of slats being between 2 and 5.
- the yield strength Re the tensile strength Rm, and the total elongation A have been determined for sheets obtained by these different modes of manufacture.
- microstructure of the plates obtained by Scanning Electron Microscopy was also observed by means of a field effect gun ("MEB-FEG” technique) and EBSD detector and quantified the average size of the slats of the martensitic structure and their factor. extension
- Tests A1 and A2 designate tests carried out on the composition of steel A under two different conditions, the test B1 was made from the composition of steel B.
- Figure 1 shows the microstructure obtained in the case of test A1.
- Figure 2 shows the microstructure of the same steel simply heated to 1250 ° C, maintained for 30 minutes at this temperature and then quenched with water (A2 test)
- the method according to the invention makes it possible to obtain a martensite with a average size of slats much thinner and less elongated than in the reference structure.
- the AR values are 353 and of 306 MPa respectively.
- the method according to the invention therefore makes it possible to obtain mechanical strength values that are clearly higher than those which would be obtained by a simple martensitic quenching.
- This increase in strength (353 or 306 MPa) is equivalent to that which would be obtained from equation (1) by simple martensitic quenching applied to steels in which an additional addition of 0.11% or 0.09 about% would have been achieved.
- Such an increase in the carbon content would, however, have adverse consequences with respect to the weldability and toughness, whereas the method according to the invention makes it possible to achieve very high values of mechanical strength without these disadvantages.
- the plates produced according to the invention because of their lower carbon content, have good weldability by the usual processes, in particular spot resistance welding.
- test B3 cooled to 50 ° C / s to 525 ° C, then cooled to above the critical martensitic quenching rate (test B3)
- FIG. 3 shows the microstructure obtained in the B3 condition according to the invention, characterized by a very fine slat size (0.9 micrometres) and a low elongation factor.
- the invention allows the manufacture of sheets, or bare or coated parts, with very high mechanical characteristics, under very satisfactory economic conditions.
Abstract
Description
Claims
Priority Applications (16)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
CN201280022858.7A CN103562417B (zh) | 2011-05-12 | 2012-04-20 | 制造极高强度马氏体钢的方法及如此获得的板材或部件 |
UAA201314471A UA113628C2 (xx) | 2011-05-12 | 2012-04-20 | Спосіб виготовлення листа або деталі з надміцної мартенситної сталі та лист або деталь, одержані за таким способом |
MA36353A MA35058B1 (fr) | 2011-05-12 | 2012-04-20 | Procede de fabrication d'acier martensitique a tres haute resistance et tôle ou piece ainsi obtenue |
MX2013013220A MX359665B (es) | 2011-05-12 | 2012-04-20 | Método para la fabricación de acero martensítico de resistencia muy alta y placa o pieza obtenida por tal método. |
RU2013155181/02A RU2580578C2 (ru) | 2011-05-12 | 2012-04-20 | Способ изготовления из сверхпрочной мартенситной стали и полученные таким образом лист или деталь |
BR112013028931-7A BR112013028931B1 (pt) | 2011-05-12 | 2012-04-20 | “processo de fabricação de uma chapa de aço com estrutura totalmente martensítica, chapa de aço com limite de elasticidade superior a 1300 mpa de aço e chapa de aço” |
ES12724656.9T ES2612514T3 (es) | 2011-05-12 | 2012-04-20 | Procedimiento de fabricación de acero martensítico de muy alta resistencia y chapa o pieza obtenida de ese modo |
KR1020157021040A KR20150095949A (ko) | 2011-05-12 | 2012-04-20 | 초고강도 마텐자이트 강의 제조 방법 및 이 방법에 의해 획득된 시트 또는 부품 |
US14/116,991 US10337090B2 (en) | 2011-05-12 | 2012-04-20 | Method for the production of very high strength martensitic steel and sheet or part thus obtained |
KR1020137032514A KR101590689B1 (ko) | 2011-05-12 | 2012-04-20 | 초고강도 마텐자이트 강의 제조 방법 및 이 방법에 의해 획득된 시트 또는 부품 |
BR122018069395-9A BR122018069395B1 (pt) | 2011-05-12 | 2012-04-20 | Processo de fabricação de uma peça de aço de estrutura totalmente martensítica e peça de aço |
EP12724656.9A EP2707513B1 (fr) | 2011-05-12 | 2012-04-20 | Procede de fabrication d'acier martensitique a tres haute resistance et tôle ou piece ainsi obtenue |
JP2014509779A JP6114261B2 (ja) | 2011-05-12 | 2012-04-20 | 非常に高い強度のマルテンサイト鋼およびこれにより得た鋼板または部品の製造方法 |
CA2835533A CA2835533C (fr) | 2011-05-12 | 2012-04-20 | Procede de fabrication d'acier martensitique a tres haute resistance et tole ou piece ainsi obtenue |
ZA2013/09348A ZA201309348B (en) | 2011-05-12 | 2013-10-21 | Method for the production of very-high-strength martensitic steel and sheet or part thus obtained |
US16/276,242 US10895003B2 (en) | 2011-05-12 | 2019-02-14 | Very high strength martensitic steel or part and method of fabrication |
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
FRPCT/FR2011/000294 | 2011-05-12 | ||
PCT/FR2011/000294 WO2012153008A1 (fr) | 2011-05-12 | 2011-05-12 | Procede de fabrication d'acier martensitique a tres haute resistance et tole ou piece ainsi obtenue |
Related Child Applications (2)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US14/116,991 A-371-Of-International US10337090B2 (en) | 2011-05-12 | 2012-04-20 | Method for the production of very high strength martensitic steel and sheet or part thus obtained |
US16/276,242 Division US10895003B2 (en) | 2011-05-12 | 2019-02-14 | Very high strength martensitic steel or part and method of fabrication |
Publications (1)
Publication Number | Publication Date |
---|---|
WO2012153012A1 true WO2012153012A1 (fr) | 2012-11-15 |
Family
ID=46197581
Family Applications (2)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
PCT/FR2011/000294 WO2012153008A1 (fr) | 2011-05-12 | 2011-05-12 | Procede de fabrication d'acier martensitique a tres haute resistance et tole ou piece ainsi obtenue |
PCT/FR2012/000153 WO2012153012A1 (fr) | 2011-05-12 | 2012-04-20 | Procede de fabrication d'acier martensitique a tres haute resistance et tôle ou piece ainsi obtenue |
Family Applications Before (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
PCT/FR2011/000294 WO2012153008A1 (fr) | 2011-05-12 | 2011-05-12 | Procede de fabrication d'acier martensitique a tres haute resistance et tole ou piece ainsi obtenue |
Country Status (16)
Country | Link |
---|---|
US (2) | US10337090B2 (fr) |
EP (1) | EP2707513B1 (fr) |
JP (1) | JP6114261B2 (fr) |
KR (2) | KR101590689B1 (fr) |
CN (1) | CN103562417B (fr) |
BR (2) | BR122018069395B1 (fr) |
CA (1) | CA2835533C (fr) |
ES (1) | ES2612514T3 (fr) |
HU (1) | HUE031878T2 (fr) |
MA (1) | MA35058B1 (fr) |
MX (1) | MX359665B (fr) |
PL (1) | PL2707513T3 (fr) |
RU (1) | RU2580578C2 (fr) |
UA (1) | UA113628C2 (fr) |
WO (2) | WO2012153008A1 (fr) |
ZA (1) | ZA201309348B (fr) |
Families Citing this family (18)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
WO2016016676A1 (fr) * | 2014-07-30 | 2016-02-04 | ArcelorMittal Investigación y Desarrollo, S.L. | Procédé de fabrication de tôles d'acier, pour durcissement sous presse, et pièces obtenues par ce procédé |
CN104357747B (zh) * | 2014-10-27 | 2017-11-03 | 中国科学院金属研究所 | 一种微合金化锰硼合金钢及其热处理方法和应用 |
WO2016079565A1 (fr) * | 2014-11-18 | 2016-05-26 | Arcelormittal | Procédé de fabrication d'un produit en acier haute résistance et produit en acier ainsi obtenu |
CN104846274B (zh) | 2015-02-16 | 2017-07-28 | 重庆哈工易成形钢铁科技有限公司 | 热冲压成形用钢板、热冲压成形工艺及热冲压成形构件 |
DE102016201024A1 (de) * | 2016-01-25 | 2017-07-27 | Schwartz Gmbh | Wärmebehandlungsverfahren und Wärmebehandlungsvorrichtung |
RU2630082C1 (ru) * | 2016-12-02 | 2017-09-05 | Федеральное Государственное Унитарное Предприятие "Центральный научно-исследовательский институт черной металлургии им. И.П. Бардина" (ФГУП "ЦНИИчермет им. И.П. Бардина") | Способ получения изделий из горячекатаного стального листа горячей штамповкой |
RU2630084C1 (ru) * | 2016-12-02 | 2017-09-05 | Федеральное Государственное Унитарное Предприятие "Центральный научно-исследовательский институт черной металлургии им. И.П. Бардина" (ФГУП "ЦНИИчермет им. И.П. Бардина") | Способ получения изделий из холоднокатаного стального листа горячей штамповкой |
WO2018160462A1 (fr) | 2017-03-01 | 2018-09-07 | Ak Steel Properties, Inc. | Acier trempé à la presse à résistance extrêmement élevée |
EP3589757A1 (fr) * | 2017-03-01 | 2020-01-08 | Ak Steel Properties, Inc. | Acier laminé à chaud à très haute résistance et son procédé de fabrication |
CN109023092B (zh) * | 2018-09-10 | 2020-07-10 | 武汉钢铁有限公司 | 轮辋用1300MPa级热成形钢及制备方法 |
CN109355578B (zh) * | 2018-12-14 | 2022-02-18 | 辽宁衡业高科新材股份有限公司 | 一种1000MPa级别热处理车轮的制备方法 |
CN111215751B (zh) | 2019-03-29 | 2022-06-28 | 宝山钢铁股份有限公司 | 一种带铝或者铝合金镀层的钢制差强焊接部件及其制造方法 |
CN110273052A (zh) * | 2019-07-10 | 2019-09-24 | 泰州市金鹰齿轮有限公司 | 一种高档锥压淬模具 |
CN112210726B (zh) * | 2020-09-29 | 2022-02-15 | 中国科学院金属研究所 | 一种超高强度纳米晶40Cr2NiMnW结构钢及其制备方法 |
CN112725698B (zh) * | 2020-12-28 | 2021-12-07 | 郑州航空工业管理学院 | 一种多尺度结构块体材料及其制备方法和应用 |
CN114107636B (zh) * | 2021-10-19 | 2023-02-24 | 北京科技大学 | 一种2000MPa级超高强韧轮辐用热轧热成形钢及其制备方法 |
CN113832407B (zh) * | 2021-11-29 | 2022-02-22 | 东北大学 | 一种厚规格热成形钢的制备方法、热轧钢板及热成形钢 |
CN115874112B (zh) * | 2022-11-02 | 2024-04-30 | 包头钢铁(集团)有限责任公司 | 一种1300兆帕级冷轧马氏体钢的制造方法 |
Citations (6)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
GB1080304A (en) | 1965-03-12 | 1967-08-23 | Natural Res Dev Corp | Ausforming high-strength alloy steels |
GB1166042A (en) | 1965-12-22 | 1969-10-01 | Nat Res Dev | Improvements in Heat Treated Alloy Steels |
US3907614A (en) * | 1972-12-20 | 1975-09-23 | Bethlehem Steel Corp | Bainitic ferrous alloy and method |
EP0971044A1 (fr) | 1998-07-09 | 2000-01-12 | Sollac | Tole d'acier laminée à chaud et à froid revêtue et présentant une très haute résistance après traitement thermique |
US20080017283A1 (en) * | 2005-07-05 | 2008-01-24 | Keiichi Maruta | Steel For Machine Structural Use With Excellent Strength, Ductility, And Toughness And Method For Producing The Same |
US20100230016A1 (en) * | 2008-09-17 | 2010-09-16 | Tatsuya Kumagai | High-strength steel plate and producing method therefor |
Family Cites Families (17)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US3276903A (en) * | 1953-02-04 | 1966-10-04 | Onera (Off Nat Aerospatiale) | Heat treatment of metals |
JPS61195958A (ja) * | 1985-02-26 | 1986-08-30 | Nippon Steel Corp | 高加工性を有する制振鋼板の製造方法 |
JPH09310116A (ja) * | 1996-05-21 | 1997-12-02 | Daido Steel Co Ltd | 遅れ破壊特性に優れた高強度部材の製造方法 |
KR100386767B1 (ko) | 1997-07-28 | 2003-06-09 | 닛폰 스틸 가부시키가이샤 | 인성이 우수한 초고강도 용접성 강의 제조방법 |
JPH11100644A (ja) * | 1997-09-26 | 1999-04-13 | Daido Steel Co Ltd | 高強度・高靱性ばね用鋼およびばねの製造方法 |
EP0937757A1 (fr) | 1998-02-19 | 1999-08-25 | Nihon Parkerizing Co., Ltd. | Composition, procédé pour le traitement hydrophilique de l'aluminium ou d'un alliage d'aluminium et utilisation de cette composition |
DK1218552T3 (da) * | 1999-07-12 | 2009-11-30 | Mmfx Steel Corp Of America | Stål med lavt indhold af kulstof med fremragnede mekaniske korrosionsegenskaber |
FR2849864B1 (fr) | 2003-01-15 | 2005-02-18 | Usinor | Acier lamine a chaud a tres haute resistance et procede de fabrication de bandes |
JP2004337923A (ja) * | 2003-05-15 | 2004-12-02 | Sumitomo Metal Ind Ltd | 熱間成形鋼材の製造方法 |
JP4673558B2 (ja) | 2004-01-26 | 2011-04-20 | 新日本製鐵株式会社 | 生産性に優れた熱間プレス成形方法及び自動車用部材 |
CN100540706C (zh) * | 2005-07-05 | 2009-09-16 | 杰富意钢铁株式会社 | 强度、延展性以及韧性优良的机械结构用钢及其制造方法 |
JP4502272B2 (ja) * | 2005-12-14 | 2010-07-14 | 株式会社神戸製鋼所 | 加工性および疲労特性に優れる熱延鋼板及びその鋳造方法 |
JP4681492B2 (ja) * | 2006-04-07 | 2011-05-11 | 新日本製鐵株式会社 | 鋼板熱間プレス方法及びプレス成形品 |
JP2007310116A (ja) | 2006-05-18 | 2007-11-29 | Seiko Epson Corp | 配向膜の形成方法、液晶パネルの製造方法、および電子機器の製造方法 |
KR100797326B1 (ko) * | 2006-09-29 | 2008-01-22 | 주식회사 포스코 | Pwht 물성 보증용 심해 라이저 파이프 강재 및 그제조방법 |
RU2350662C1 (ru) * | 2007-06-15 | 2009-03-27 | Открытое акционерное общество "Северсталь" (ОАО "Северсталь") | Способ производства листов |
US8500924B2 (en) * | 2008-11-11 | 2013-08-06 | Nippon Steel & Sumitomo Metal Corporation | High-strength steel plate and producing method therefor |
-
2011
- 2011-05-12 WO PCT/FR2011/000294 patent/WO2012153008A1/fr active Application Filing
-
2012
- 2012-04-20 BR BR122018069395-9A patent/BR122018069395B1/pt active IP Right Grant
- 2012-04-20 JP JP2014509779A patent/JP6114261B2/ja active Active
- 2012-04-20 RU RU2013155181/02A patent/RU2580578C2/ru active
- 2012-04-20 MX MX2013013220A patent/MX359665B/es active IP Right Grant
- 2012-04-20 ES ES12724656.9T patent/ES2612514T3/es active Active
- 2012-04-20 UA UAA201314471A patent/UA113628C2/uk unknown
- 2012-04-20 WO PCT/FR2012/000153 patent/WO2012153012A1/fr active Application Filing
- 2012-04-20 EP EP12724656.9A patent/EP2707513B1/fr active Active
- 2012-04-20 PL PL12724656T patent/PL2707513T3/pl unknown
- 2012-04-20 MA MA36353A patent/MA35058B1/fr unknown
- 2012-04-20 KR KR1020137032514A patent/KR101590689B1/ko active IP Right Grant
- 2012-04-20 BR BR112013028931-7A patent/BR112013028931B1/pt active IP Right Grant
- 2012-04-20 CN CN201280022858.7A patent/CN103562417B/zh active Active
- 2012-04-20 US US14/116,991 patent/US10337090B2/en active Active
- 2012-04-20 HU HUE12724656A patent/HUE031878T2/en unknown
- 2012-04-20 CA CA2835533A patent/CA2835533C/fr active Active
- 2012-04-20 KR KR1020157021040A patent/KR20150095949A/ko not_active Application Discontinuation
-
2013
- 2013-10-21 ZA ZA2013/09348A patent/ZA201309348B/en unknown
-
2019
- 2019-02-14 US US16/276,242 patent/US10895003B2/en active Active
Patent Citations (6)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
GB1080304A (en) | 1965-03-12 | 1967-08-23 | Natural Res Dev Corp | Ausforming high-strength alloy steels |
GB1166042A (en) | 1965-12-22 | 1969-10-01 | Nat Res Dev | Improvements in Heat Treated Alloy Steels |
US3907614A (en) * | 1972-12-20 | 1975-09-23 | Bethlehem Steel Corp | Bainitic ferrous alloy and method |
EP0971044A1 (fr) | 1998-07-09 | 2000-01-12 | Sollac | Tole d'acier laminée à chaud et à froid revêtue et présentant une très haute résistance après traitement thermique |
US20080017283A1 (en) * | 2005-07-05 | 2008-01-24 | Keiichi Maruta | Steel For Machine Structural Use With Excellent Strength, Ductility, And Toughness And Method For Producing The Same |
US20100230016A1 (en) * | 2008-09-17 | 2010-09-16 | Tatsuya Kumagai | High-strength steel plate and producing method therefor |
Non-Patent Citations (4)
Title |
---|
MORITO S ET AL: "Effect of block size on the strength of lath martensite in low carbon steels", MATERIALS SCIENCE AND ENGINEERING A: STRUCTURAL MATERIALS:PROPERTIES, MICROSTRUCTURE & PROCESSING, LAUSANNE, CH, vol. 438-440, 25 November 2006 (2006-11-25), pages 237 - 240, XP025099372, ISSN: 0921-5093, [retrieved on 20061125], DOI: 10.1016/J.MSEA.2005.12.048 * |
S. MORITO ET AL: "Effect of Austenite Grain Size on the Morphology and Crystallography of Lath Martensite in Low Carbon Steels", ISIJ INTERNATIONAL, vol. 45, no. 1, 1 January 2005 (2005-01-01), pages 91 - 94, XP055018139, ISSN: 0915-1559, DOI: 10.2355/isijinternational.45.91 * |
TSUJI N ET AL: "Enhanced structural refinement by combining phase transformation and plastic deformation in steels", SCRIPTA MATERIALIA, ELSEVIER, AMSTERDAM, NL, vol. 60, no. 12, 1 June 2009 (2009-06-01), pages 1044 - 1049, XP026034677, ISSN: 1359-6462, [retrieved on 20090220], DOI: 10.1016/J.SCRIPTAMAT.2009.02.028 * |
VENKATARAMAN G ET AL: "Thermomechanical treatment of a low carbon Cr@?Ni@?Mo steel", MATERIALS SCIENCE ENGINEERING, ELSEVIER SEQUOIA, LAUSANNE, CH, vol. 16, no. 1-2, 1 October 1974 (1974-10-01), pages 133 - 141, XP024085281, ISSN: 0025-5416, [retrieved on 19741001], DOI: 10.1016/0025-5416(74)90147-5 * |
Also Published As
Publication number | Publication date |
---|---|
WO2012153008A1 (fr) | 2012-11-15 |
EP2707513A1 (fr) | 2014-03-19 |
BR122018069395B1 (pt) | 2019-04-24 |
MX359665B (es) | 2018-10-05 |
MX2013013220A (es) | 2014-06-23 |
CN103562417B (zh) | 2015-07-29 |
CA2835533A1 (fr) | 2012-11-15 |
US20140076470A1 (en) | 2014-03-20 |
US10337090B2 (en) | 2019-07-02 |
KR20150095949A (ko) | 2015-08-21 |
KR20140019838A (ko) | 2014-02-17 |
US20190226060A1 (en) | 2019-07-25 |
US10895003B2 (en) | 2021-01-19 |
JP6114261B2 (ja) | 2017-04-12 |
BR112013028931B1 (pt) | 2019-03-06 |
CN103562417A (zh) | 2014-02-05 |
RU2013155181A (ru) | 2015-06-20 |
RU2580578C2 (ru) | 2016-04-10 |
ZA201309348B (en) | 2014-07-30 |
PL2707513T3 (pl) | 2017-04-28 |
ES2612514T3 (es) | 2017-05-17 |
KR101590689B1 (ko) | 2016-02-01 |
EP2707513B1 (fr) | 2016-11-09 |
HUE031878T2 (en) | 2017-08-28 |
CA2835533C (fr) | 2018-12-04 |
JP2014517149A (ja) | 2014-07-17 |
MA35058B1 (fr) | 2014-04-03 |
UA113628C2 (xx) | 2017-02-27 |
BR112013028931A2 (pt) | 2017-02-07 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
EP2707513B1 (fr) | Procede de fabrication d'acier martensitique a tres haute resistance et tôle ou piece ainsi obtenue | |
CA2686940C (fr) | Procede de fabrication de toles d'acier laminees a froid et recuites a tres haute resistance, et toles ainsi produites | |
EP3783116B1 (fr) | Tôles prerevêtues permettant la fabrication de pieces d'acier revêtues et durcies a la presse | |
CA2680623C (fr) | Acier pour formage a chaud ou trempe sous outil, a ductilite amelioree | |
EP2707515B1 (fr) | Procede de fabrication d'acier martensitique a tres haute limite élastique et tole ou piece ainsi obtenue. | |
CA2533023C (fr) | Procede de fabrication de toles d'acier austenitique fer-carbone-manganese, a haute resistance, excellente tenacite et aptitude a la mise en forme a froid, et toles ainsi produites | |
EP3307921A2 (fr) | Acier à haute résistance et procédé de fabrication | |
CA3065036C (fr) | Procede de fabrication de pieces d'acier a haute resistance mecanique et ductilite amelioree, et pieces obtenues par ce procede | |
WO2011104443A1 (fr) | Procédé de fabrication d'une pièce a partir d'une tôle revêtue d'aluminium ou d'alliage d'aluminium |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
121 | Ep: the epo has been informed by wipo that ep was designated in this application |
Ref document number: 12724656 Country of ref document: EP Kind code of ref document: A1 |
|
REEP | Request for entry into the european phase |
Ref document number: 2012724656 Country of ref document: EP |
|
WWE | Wipo information: entry into national phase |
Ref document number: 2012724656 Country of ref document: EP |
|
ENP | Entry into the national phase |
Ref document number: 2835533 Country of ref document: CA |
|
ENP | Entry into the national phase |
Ref document number: 2014509779 Country of ref document: JP Kind code of ref document: A |
|
WWE | Wipo information: entry into national phase |
Ref document number: 14116991 Country of ref document: US |
|
NENP | Non-entry into the national phase |
Ref country code: DE |
|
WWE | Wipo information: entry into national phase |
Ref document number: MX/A/2013/013220 Country of ref document: MX |
|
ENP | Entry into the national phase |
Ref document number: 20137032514 Country of ref document: KR Kind code of ref document: A |
|
WWE | Wipo information: entry into national phase |
Ref document number: A201314471 Country of ref document: UA |
|
ENP | Entry into the national phase |
Ref document number: 2013155181 Country of ref document: RU Kind code of ref document: A |
|
REG | Reference to national code |
Ref country code: BR Ref legal event code: B01A Ref document number: 112013028931 Country of ref document: BR |
|
ENP | Entry into the national phase |
Ref document number: 112013028931 Country of ref document: BR Kind code of ref document: A2 Effective date: 20131111 |