US20110073223A1 - Steel sheet for galvanizing with excellent workability, and method for manufacturing the same - Google Patents

Steel sheet for galvanizing with excellent workability, and method for manufacturing the same Download PDF

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US20110073223A1
US20110073223A1 US12/064,653 US6465306A US2011073223A1 US 20110073223 A1 US20110073223 A1 US 20110073223A1 US 6465306 A US6465306 A US 6465306A US 2011073223 A1 US2011073223 A1 US 2011073223A1
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steel sheet
steel
temperature
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Il-Ryoung Sohn
Kwang-Geun Chin
Hee-Jae Kang
Sung-ll Kim
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Posco Holdings Inc
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Posco Co Ltd
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    • 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
    • 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
    • C21D8/04—Modifying the physical properties by deformation combined with, or followed by, heat treatment during manufacturing of plates or strips to produce plates or strips for deep-drawing
    • C21D8/0421—Modifying the physical properties by deformation combined with, or followed by, heat treatment during manufacturing of plates or strips to produce plates or strips for deep-drawing characterised by the working steps
    • C21D8/0426—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
    • C21D8/04—Modifying the physical properties by deformation combined with, or followed by, heat treatment during manufacturing of plates or strips to produce plates or strips for deep-drawing
    • C21D8/0447—Modifying the physical properties by deformation combined with, or followed by, heat treatment during manufacturing of plates or strips to produce plates or strips for deep-drawing characterised by the heat treatment
    • C21D8/0473—Final recrystallisation annealing
    • 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
    • C22C38/001—Ferrous alloys, e.g. steel alloys containing N
    • 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
    • C22C38/002—Ferrous alloys, e.g. steel alloys containing In, Mg, or other elements not provided for in one single group C22C38/001 - C22C38/60
    • 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
    • C22C38/004—Very low carbon steels, i.e. having a carbon content of less than 0,01%
    • 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
    • C22C38/008—Ferrous alloys, e.g. steel alloys containing tin
    • 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
    • C22C38/12—Ferrous alloys, e.g. steel alloys containing tungsten, tantalum, molybdenum, vanadium, or niobium
    • 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
    • C22C38/14—Ferrous alloys, e.g. steel alloys containing titanium or zirconium
    • 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
    • C22C38/60—Ferrous alloys, e.g. steel alloys containing lead, selenium, tellurium, or antimony, or more than 0.04% by weight of sulfur
    • C—CHEMISTRY; METALLURGY
    • C23—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
    • C23C—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; SURFACE TREATMENT OF METALLIC MATERIAL BY DIFFUSION INTO THE SURFACE, BY CHEMICAL CONVERSION OR SUBSTITUTION; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL
    • C23C2/00—Hot-dipping or immersion processes for applying the coating material in the molten state without affecting the shape; Apparatus therefor
    • C23C2/02—Pretreatment of the material to be coated, e.g. for coating on selected surface areas
    • C—CHEMISTRY; METALLURGY
    • C23—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
    • C23C—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; SURFACE TREATMENT OF METALLIC MATERIAL BY DIFFUSION INTO THE SURFACE, BY CHEMICAL CONVERSION OR SUBSTITUTION; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL
    • C23C2/00—Hot-dipping or immersion processes for applying the coating material in the molten state without affecting the shape; Apparatus therefor
    • C23C2/02—Pretreatment of the material to be coated, e.g. for coating on selected surface areas
    • C23C2/022—Pretreatment of the material to be coated, e.g. for coating on selected surface areas by heating
    • C23C2/0224—Two or more thermal pretreatments
    • 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
    • C21D2211/004—Dispersions; Precipitations

Definitions

  • the present invention generally relates to a high strength ductile steel sheet for extra deep drawing for interior or exterior plates of automobile bodies and the like, and to a method for manufacturing the same. More particularly, the present invention relates to a steel sheet for galvanizing with excellent workability, which has a tensile strength of 28 ⁇ 50 kgf/mm 2 , and has excellent properties in terms of formability, secondary work embrittlement resistance, fatigue properties of welded joints and surface quality, and to a method for manufacturing the same.
  • steel sheets for the automobile body have been required to have further enhanced formability.
  • the steel sheets for the automobile body also have been required to have excellent secondary work embrittlement and fatigue properties of welded joints in terms of using conditions of the automobiles, and to have an appealing plated surface.
  • steel sheets having enhanced formability and strength are produced in such a way of adding Si, Mn, Ti, Al and the like to highly pure steel which is minimized in contents of impurities in the steel.
  • annealing is performed at a temperature of 700° C. or more for recrystallization of work hardened structures.
  • the added elements described as above have a higher affinity to oxygen than Fe, the added elements are grown to surface agglomerates, such as MnO, SiO 2 , Al 2 O 3 , TiO and the like, in singular or composite forms during the cold annealing process.
  • coarsening of the surface agglomerates causes fine dents on the surface of the plated steel sheet via attachment of the coarsened surface agglomerates to a hearth roll of a continuous furnace, thereby providing a significantly adverse influence on surface quality of the steel sheet.
  • JP2002-146477, JP2001-64750 and JP2002-155317 disclose techniques aiming to enhance plating properties by adding specific elements such as Cr, Sb and the like to a steel sheet
  • JP2001-288550 discloses a technique aiming to suppress formation of the surface agglomerates during cold annealing through pre-oxidation of hot coil before cold rolling.
  • the present invention has been made to solve the above problems, and it is an object of the present invention to provide a steel sheet for galvanizing with excellent workability, which has a tensile strength of 28 ⁇ 50 kgf/mm 2 , and has excellent properties in terms of formability, secondary work embrittlement resistance, fatigue properties of welded joints and surface quality.
  • a steel sheet for galvanizing with excellent workability comprising, by weight %: C, 0.010% or less, Si: 0.1% or less, Mn: 0.06 ⁇ 1.5%, P: 0.15% or less, S: 0.020% or less, Sol.
  • Al 0.10 ⁇ 0.40%, N: 0.010% or less, Ti: 0.003 ⁇ 0.010%, Nb: 0.003 ⁇ 0.040%, B: 0.0002 ⁇ 0.0020%, Mo: 0.05% or less, one or both of Sb: 0.005 ⁇ 0.05% and Sn: 0.005 ⁇ 0.05%, a total amount of Sb and Sn being in the range of 0.005 ⁇ 0.1% when both of Sb and Sn are added to the steel sheet, and the balance of Fe and other unavoidable impurities, wherein the steel sheet has surface agglomerates having an average diameter of 1 ⁇ m or less, and a tensile strength of 28 ⁇ 50 kgf/mm 2 .
  • the average diameter of the surface agglomerates is suppressed in growth by 10% or less for an increase in annealing temperature of 10° C.
  • a method for manufacturing a steel sheet for galvanizing with excellent workability comprises: reheating a steel slab comprising by weight %: C, 0.010% or less, Si: 0.1% or less, Mn: 0.06 ⁇ 1.5%, P: 0.15% or less, S: 0.020% or less, Sol.
  • Al 0.10 ⁇ 0.40%, N: 0.010% or less, Ti: 0.003 ⁇ 0.010%, Nb: 0.003 ⁇ 0.040%, B: 0.0002 ⁇ 0.0020%, Mo: 0.05% or less, one or both of Sb: 0.005 ⁇ 0.05% and Sn: 0.005 ⁇ 0.05%, a total amount of Sb and Sn being in the range of 0.005 ⁇ 0.1% when both of Sb and Sn are added to the steel sheet, and the balance of Fe and other unavoidable impurities; hot rolling the reheated steel slab with finish rolling at a finish rolling temperature of a single phase austenite region to form a steel sheet, followed by coiling the hot rolled steel sheet; cold rolling the hot rolled steel sheet; and continuously annealing the cold rolled steel sheet at a temperature of 700° C. or more.
  • the present invention provides a steel sheet for galvanizing with excellent workability, which has a tensile strength of 28 ⁇ 50 kgf/mm 2 , and excellent properties in terms of formability, secondary work embrittlement resistance, fatigue properties of welded joints and surface quality.
  • FIG. 1 is a graph depicting change in amount of surface agglomerates according to kinds of steel and annealing temperature
  • FIG. 2 is micrographs showing distribution of surface agglomerates on surfaces of air cooled steel sheets and water cooled steel sheets according to kinds of steel and after hot coiling;
  • FIG. 3 is micrographs showing distribution of surface agglomerates on steel sheets according to kinds of steel and annealing temperatures.
  • the steel sheet according to the present invention will be described in terms of composition.
  • C acts as an interstitial solid solution element in steel, and obstructs formation of 111 texture, which is advantageous in terms of workability in the course of forming the texture in a steel sheet upon cold rolling and annealing.
  • An excessive content of carbon requires an increase in contents of Ti and Nb which are carbide and nitride formation elements, causing a disadvantage of increased manufacturing costs.
  • the carbon content is preferably 0.010% or less.
  • Si is an element which causes temper color upon annealing, and non-plated regions upon plating as well as surface scale.
  • the silicon content is preferably 0.1% or less.
  • Mn is added as a substitutional solid solution strengthening element for ensuring strength of steel.
  • a Mn content exceeds 1.5%, an r-value of the steel is rapidly deteriorated along with elongation, and if the Mn content is less than 0.06%, the steel suffers from embrittlement due to S in the steel.
  • the Mn content is preferably in the range of 0.06 ⁇ 1.5%.
  • P is also a representative solid solution strengthening element which is added to the steel along with Mn for increasing the strength.
  • P is added to Ti—Nb steel as in the steel of the present invention, it results in growth of the 111 texture, advantageous in terms of the r-value, through grain refinement, grain boundary segregation, and the like.
  • P content exceeds 0.15%, the steel suffers from rapid reduction in elongation along with significant increase in brittleness.
  • the P content is preferably in the range of 0.03 ⁇ 0.15%.
  • S content in the steel is generally restricted to a low degree of 0.005% or less. According to the present invention, however, since the steel contains Mn, all amounts of S in the steel are precipitated as MnS, thereby making it possible to avoid deterioration in formability due to solid solution of S.
  • S content is preferably 0.020% or less, which can deviate from a region causing edge cracks during rolling.
  • a Sol. Al content of the steel is generally controlled to be in the range of 0.02 ⁇ 0.07% while dissolved oxygen in the steel is maintained at a sufficiently low amount in consideration of manufacturing costs.
  • Sol. Al serves to allow deep drawability to be stably secured at a lower annealing temperature.
  • the Sol. Al content is 0.10% or more in the steel, it coarsens the precipitates in the steel, remarkably obstructs effect of suppressing recrystallization by P, thereby activating the recrystallization, and aids in development of the 111 texture. If the Sol. Al content exceeds 0.40%, it causes an increase of the manufacturing costs, and deterioration in efficiency of continuous casting operation. Thus, the Sol. Al content is preferably in the range of 0.10 ⁇ 0.40%.
  • the Sol. Al content influences formation of Ti or Nb-based precipitates as the carbide and nitride to coarsen the precipitates, it serves as a critical component which provides further enhanced workability of the steel with small added amounts of Ti and Nb in comparison to the conventional IF steel.
  • N deteriorates the workability of the steel if it exists in a solid solution state in the steel. Furthermore, if an excessive content of N resides in the steel, it is necessary to increase added amounts of Ti and Nb for fixing N as precipitates in the steel. Thus, the N content is preferably 0.010% or less.
  • B is a grain boundary strengthening element, and effective to enhance fatigue properties of spot welded joints while preventing grain boundary embrittlement by P.
  • B content In order to obtain the effect by addition of B, it is necessary to have B content of 0.0002% or more. However, if the B content exceeds 0.0020%, the steel suffers from rapid deterioration of the workability and surface properties of the plated steel sheet.
  • the B content is preferably 0.0002 ⁇ 0.0020%.
  • Mo is added to enhance the secondary work embrittlement resistance and the plating properties. If Mo content exceeds 0.05%, the effect of enhancing the secondary work embrittlement resistance and the plating properties is significantly reduced, and it is disadvantageous in terms of the manufacturing costs. Thus, the Mo content is preferably 0.05% or less.
  • Ti and Nb are very important elements in view of the workability. Ti and Nb must be added to the steel in an amount of 0.003 ⁇ 0.010%, and an amount of 0.003 ⁇ 0.040%, respectively, in consideration of a minimum and optimum amount for securing the workability (in particular, r-value) enhancing effect.
  • Sb is a very important element, and exhibits remarkable effects to suppress generation of surface agglomerates such as MnO, SiO 2 , Al 2 O 3 , and the like, and to suppress coarsening of the surface agglomerates by a temperature increase and other variations in hot processing.
  • the Sb content must be 0.005% or more.
  • Sb is added exceeding a specific content, the above effects cannot be obtained, and thus the Sb content has an upper limit of 0.05%.
  • Sn exhibits similar effects to those of Sb in the steel.
  • the Sn content must be 0.005% or more, but if Sn is added above a specific content, the above effects cannot be obtained, and thus the Sb content has an upper limit of 0.05%.
  • a total content of Sb and Sn is preferably in the range of 0.005 ⁇ 0.1%.
  • the steel slab After reheating a steel slab having the composition as described above, the steel slab is subjected to hot rolling with finish rolling at a finish hot rolling temperature of a single phase austenite region, coiling, and cold rolling, thereby providing a cold rolled steel sheet. Then, continuous annealing is performed at a temperature of 700° C. or more.
  • the surface agglomerates (singular or composite oxides of Si, Al, Mn and the like) on the steel sheet increase in amount, exhibiting a remarkable tendency of coarsening. As a result, it is likely to generate surface defects such as non-plate regions or surface dents.
  • the present invention growth of the surface agglomerates can be suppressed in the annealing temperature region, thereby ensuring excellent surface quality of the steel sheet.
  • the reheating of the steel slab is performed at a temperature in the range of 1,100 ⁇ 1,300° C.
  • the finish rolling is performed at a temperature in the range of 830 ⁇ 920° C.
  • the coiling is performed at a temperature in the range of 500 ⁇ 700° C.
  • the hot rolled steel sheet may be subjected to air cooling or water cooling after hot coiling.
  • a reduction ratio is preferably 65% or more upon the cold rolling in order to obtain a high r-value of 1.9 or more.
  • the annealing temperature is 700° C. or more, and preferably in the range of 780 ⁇ 860° C.
  • growth of an average diameter of granular surface agglomerates is suppressed by 10% or less for an increase in annealing temperature of 10° C. in the annealing temperature range described as above.
  • continuous annealing of the cold rolled steel sheet is performed at a temperature in the range of 880 ⁇ 930° C.
  • the present invention is more economic and has superior operability.
  • a steel sheet for galvanizing with excellent workability, which has surface agglomerates having an average diameter of 1 ⁇ m or less, and a tensile strength of 28 ⁇ 50 kgf/mm 2 .
  • the surface agglomerates mainly comprise singular or composite oxides of Si, Al, Mn, Ti and the like.
  • the surface agglomerates are preferably suppressed in growth of the average diameter by 10% or less for an increase in annealing temperature of 10° C.
  • the steel slabs After reheating steel slabs having the composition as shown in Table 1 to 1,200° C., the steel slabs were subjected to hot rolling with finish rolling at a finish hot rolling temperature of 890° C. and air cooling. Then, the hot rolled steel sheets were subjected to cold rolling at a reduction ratio of 80%, thereby producing cold rolled steel sheets.
  • annealing was performed for 86 seconds at a temperature in the range of 860° C. in N 2 -10% H 2 atmosphere. Then, shapes of surface agglomerates formed on the steel sheets were investigated, and results of the measurements are shown in FIG. 1 .
  • annealing was performed for 86 seconds at a temperature in the range of 800 ⁇ 850° C. in N 2 -10% H 2 atmosphere. Then, shapes of surface agglomerates formed on the surface of the steel samples were investigated, and results of the measurements are shown in FIG. 3 .
  • Steelkinds 2 and 3 satisfying the conditions of the present invention have a lower amount of surface agglomerates of Mn and Al than that of Steel Kind 1 which does not satisfy the conditions of the present invention.
  • the Steel Kind 5 satisfying the conditions of the present invention has a lower amount and a smaller size of surface agglomerates than those of the Steel Kind 5 which does not satisfy the conditions of the present invention.
  • the steel sheet of the Steel Kind 4 subjected to air cooling after hot coiling has surface agglomerates remarkably increased in size compared with the steel sheet subjected to water-cooling after coiling.
  • the steel sheet of the Steel Kind 5 subjected to water-cooling after hot coiling has surface agglomerates which have substantially the same size as that of surface agglomerates on the steel sheet subjected to air cooling after coiling.
  • the surface agglomerates is increased in size according to an increase in annealing temperature.
  • the size of the surface agglomerates is not substantially changed irrespective of the increase in annealing temperature.

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  • Chemical & Material Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Materials Engineering (AREA)
  • Metallurgy (AREA)
  • Organic Chemistry (AREA)
  • Physics & Mathematics (AREA)
  • Thermal Sciences (AREA)
  • Crystallography & Structural Chemistry (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Heat Treatment Of Sheet Steel (AREA)
US12/064,653 2005-08-25 2006-08-24 Steel sheet for galvanizing with excellent workability, and method for manufacturing the same Abandoned US20110073223A1 (en)

Applications Claiming Priority (3)

Application Number Priority Date Filing Date Title
KR1020050078433A KR100711356B1 (ko) 2005-08-25 2005-08-25 가공성이 우수한 아연도금용 강판 및 그 제조방법
KR10-2005-0078433 2005-08-25
PCT/KR2006/003348 WO2007024114A1 (fr) 2005-08-25 2006-08-24 Tole d'acier pour galvanisation a excellente usinabilite, et procede de fabrication

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EP (1) EP1929059A4 (fr)
JP (1) JP5388577B2 (fr)
KR (1) KR100711356B1 (fr)
CN (1) CN101243198B (fr)
WO (1) WO2007024114A1 (fr)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP3875614A4 (fr) * 2018-11-02 2022-08-17 Nippon Steel Corporation Tôle d'acier électromagnétique non orientée

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JP5042232B2 (ja) * 2005-12-09 2012-10-03 ポスコ 成形性及びメッキ特性に優れた高強度冷延鋼板、これを用いた亜鉛系メッキ鋼板及びその製造方法
KR100797238B1 (ko) * 2006-12-26 2008-01-23 주식회사 포스코 가공성이 우수한 심가공용 박강판의 제조방법
CN102791895B (zh) * 2009-12-04 2014-12-24 Posco公司 具有优异耐热性的加工用冷轧钢板及其制造方法
JP4998757B2 (ja) * 2010-03-26 2012-08-15 Ｊｆｅスチール株式会社 深絞り性に優れた高強度鋼板の製造方法
KR20120127095A (ko) * 2011-05-13 2012-11-21 주식회사 포스코 표면특성이 우수한 고강도 고인성 선재 및 그 제조방법
GB2529174A (en) 2014-08-12 2016-02-17 Ibm Batch compression management of messages

Citations (6)

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JP5388577B2 (ja) 2014-01-15
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