KR101461583B1 - Method for manufacturing flat steel products from a multiphase steel microalloyed with boron - Google Patents
Method for manufacturing flat steel products from a multiphase steel microalloyed with boron Download PDFInfo
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- KR101461583B1 KR101461583B1 KR1020097007485A KR20097007485A KR101461583B1 KR 101461583 B1 KR101461583 B1 KR 101461583B1 KR 1020097007485 A KR1020097007485 A KR 1020097007485A KR 20097007485 A KR20097007485 A KR 20097007485A KR 101461583 B1 KR101461583 B1 KR 101461583B1
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- 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
- C21D8/041—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 involving a particular fabrication or treatment of ingot or slab
- C21D8/0415—Rapid solidification; Thin strip casting
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- 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
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B22—CASTING; POWDER METALLURGY
- B22D—CASTING OF METALS; CASTING OF OTHER SUBSTANCES BY THE SAME PROCESSES OR DEVICES
- B22D11/00—Continuous casting of metals, i.e. casting in indefinite lengths
- B22D11/001—Continuous casting of metals, i.e. casting in indefinite lengths of specific alloys
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B22—CASTING; POWDER METALLURGY
- B22D—CASTING OF METALS; CASTING OF OTHER SUBSTANCES BY THE SAME PROCESSES OR DEVICES
- B22D11/00—Continuous casting of metals, i.e. casting in indefinite lengths
- B22D11/06—Continuous casting of metals, i.e. casting in indefinite lengths into moulds with travelling walls, e.g. with rolls, plates, belts, caterpillars
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- 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
- C21D8/0436—Cold rolling
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- 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
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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
- C22C38/06—Ferrous alloys, e.g. steel alloys containing aluminium
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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
- C22C38/18—Ferrous alloys, e.g. steel alloys containing chromium
- C22C38/28—Ferrous alloys, e.g. steel alloys containing chromium with titanium or zirconium
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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
- C22C38/18—Ferrous alloys, e.g. steel alloys containing chromium
- C22C38/32—Ferrous alloys, e.g. steel alloys containing chromium with boron
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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
- C22C38/18—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
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- 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
Abstract
Description
본 발명은 고(高)-인장강도의 보론 미량 합금 강으로부터 스트립 또는 시트 금속 소재와 같은 평판형 강 제품을 제조하기 위한 방법에 관한 것이다. 그러한 강은 다상(multi-phase) 강의 그룹에 속한다. 이는 통상적으로 미세조직의 상들의 형태, 양 및 배열에 의해 물성이 결정되는 강이다. 따라서, 미세조직 내에 적어도 2상(예를 들면, 페라이트, 마르텐사이트, 베이나이트)이 존재한다. 그 결과, 다상 강은 종래의 강에 비하여 강도/성형성의 조합이 우수하다.The present invention relates to a method for producing flat steel products such as strips or sheet metal materials from boron microalloyed steels of high-tensile strength. Such rivers belong to a group of multi-phase lectures. It is typically a steel whose properties are determined by the shape, quantity and arrangement of phases of microstructures. Therefore, at least two phases (for example, ferrite, martensite, bainite) exist in the microstructure. As a result, the polyphase steel is superior in strength / formability combination to the conventional steel.
이러한 제조 공정은 특히 포정 반응으로 응고하는 조성물의 주조와 관련하여 문제를 일으킨다. 이러한 강종(steel grade)의 경우에, 연속 주조 중에 종방향 균열이 발생할 위험이 있다. 그러한 종방향 균열의 발생은 슬라브 또는 박슬라브로부터 제조된 열연 스트립의 품질을 심하게 저하시켜, 열연 스트립의 사용이 불가능할 수도 있다. 이러한 위험을 방지하기 위해서는, 증가된 화염 처리(flame treatment)와 같은 다양한 대책이 필요한데, 이는 그러한 강종의 가공(conversion)을 비경제적이 되게 할 수도 있다. Al 함량이 높은 강을 주조할 때에는 분체 플럭 스(powdered flux)와의 반응에 의하여 원치 않는 효과가 발생할 수도 있으며, 그 결과 이러한 강으로 제조된 평판형 제품의 품질은 바람직하지 않은 영향을 받기도 한다. This manufacturing process poses a problem, especially with regard to casting of the composition which solidifies in a round reaction. In the case of these steel grades, there is a risk of longitudinal cracks occurring during continuous casting. The occurrence of such longitudinal cracks severely degrades the quality of hot-rolled strips produced from slabs or slabs, and the use of hot-rolled strips may not be possible. To avoid this danger, various measures such as increased flame treatment are required, which may make the conversion of such grades uneconomical. When casting a high Al content steel, undesirable effects may occur due to reaction with powdered flux, and as a result, the quality of flat products made of such steels may be adversely affected.
다상 강은 강도가 높기 때문에 한편으로는 더 작은 재료 두께의 사용을 가능하게 함과 동시에 결과적으로 차량 중량의 감소를 가능하게 하고, 다른 한편으로는 충돌 시에 차량 본체의 안전성(충돌 거동)을 향상시키므로, 이러한 특별한 특성에 의해 자동차 구조용으로 상당한 주목을 받고 있다. 따라서, 본체 전체의 강도가 적어도 동일한 다상 강은 종래의 강으로 제조된 본체에 비하여 그와 같은 다상 강으로 제조된 구성품의 시트 금속 두께의 감소를 가능하게 한다. Since the polyphase steel has high strength, it is possible to use a smaller material thickness on the one hand, and consequently to reduce the weight of the vehicle, and on the other hand, to improve the safety (impact behavior) And therefore, it has received considerable attention for automobile construction due to such special characteristics. Thus, the polyphase steel having at least the same strength as the whole body enables a reduction in the sheet metal thickness of the components made of such polyphase steel compared to the body made of conventional steel.
일반적으로, 다상 강은 전로 제강소(converter steel mill)에서 용해되고 연속 주조기에서 슬라브 또는 박슬라브(thin slab)로 주조되고, 그 후에 열연 스트립으로 열연되고 권취된다. 이 경우에, 열연 스트립의 기계적 성질은, 특정 미세조직 분율의 조정을 목적으로 하는 열연 후의 열연 스트립의 선택적인 제어 냉각(controlled cooling)에 의해 변화할 수 있다. 열연 스트립은 냉연 스트립으로 냉연되어 더 얇은 시트 금속 두께가 얻어질 수도 있다(유럽 특허공보 제EP 0 910 675 B1호, 제EP 0 966 547 B1호, 제EP 1 169 486 B1호, 제EP 1 319 725 B1호 및 유럽 공개특허공보 제EP 1 398 390 A1호).Generally, polyphase steels are melted in a converter steel mill and cast into slabs or thin slabs in a continuous casting machine, then hot rolled and wound into hot-rolled strips. In this case, the mechanical properties of the hot-rolled strip can be changed by selective controlled cooling of the hot-rolled strip after hot-rolling for the purpose of adjusting the specific microstructure fraction. The hot rolled strip may be cold rolled into a cold rolled strip to obtain a thinner sheet metal thickness (EP 0 910 675 B1, EP 0 966 547 B1, EP 1 169 486 B1, EP 1 319 725 B1 and European Patent Publication No. EP 1 398 390 A1).
인장강도가 800MPa를 초과하는 고-인장강도의 다상 강으로 평판형 제품을 제조함에 있어서 문제점은 그러한 강의 압연 시에 높은 압연력(rolling force)이 가해져야 한다는 것이다. 이러한 요건에 의하면, 논의되고 있는 유형의 강으로 제조 된 고-인장강도의 열연 스트립은, 현재 일반적으로 사용 가능한 통상의 제조 장치로는 흔히 자동차 산업에서 오늘날 요구되는 요건을 충분히 충족하지 않는 폭과 두께로 제조될 수 있을 뿐이다. 특히, 두께가 얇고 폭이 충분한 스트립은 종래의 설비에서는 용이하게 제조될 수 없다. 또한, 종래의 방법으로는, 다상 강으로 강도가 800MPa를 초과하는 냉연 스트립을 제조하는 것은 실용적으로 곤란하다는 점이 밝혀졌다. The problem in producing flat plate products with poly-phase steels of high-tensile strength with tensile strengths exceeding 800 MPa is that a high rolling force must be applied during rolling of such steels. According to these requirements, hot-rolled strips of high-tensile strength, made of steel of the type being discussed, have a width and thickness that do not fully meet the requirements of today's automotive industry, . ≪ / RTI > In particular, strips of small thickness and sufficient width can not be easily manufactured in conventional installations. Further, it has been found that it is practically difficult to produce a cold-rolled strip having a strength exceeding 800 MPa as a poly-phase steel by the conventional method.
다상 강으로 강 스트립을 제조하는 대안적인 방법이 유럽 특허공보 제EP 1 072 689 B1호(독일 특허공보 제DE 600 09 611 T2호)에 제안되어 있다. 이러한 공지 방법에 따르면, 우선, (중량%로) 0.05%와 0.25%의 C, 합계 0.5% ~ 3%의 Mn, Cu 및 Ni, 합계 0.1% ~ 4%의 Si와 Al, 합계 0.1%까지의 P, Sn, As 및 Sb, 합계 0.3% 미만의 Ti, Nb, V, Zr 및 REM과 더불어, 각각이 1% 미만인 Cr, Mo 및 V, 잔부 Fe 및 불가피한 불순물을 함유하는 용강이 두께 0.5mm ~ 10mm, 특히 1mm ~ 5mm의 주조 스트립으로 주조된다. 그 후 주조 스트립은 1회 이상의 패스로 인라인으로 열연 스트립으로 열연되고, 변형도는 25% 내지 70%의 범위이다. 최종 열연 온도는 이 경우에 Ar3 온도보다 높다. 열연 종료 시에 얻어진 열연 스트립은 그 후 두 단계로 냉각된다. 이러한 냉각의 제1 단계에서, 400℃ ~ 550℃ 범위의 온도에 이를 때까지 초당 5℃ ~ 100℃의 냉각 속도가 유지된다. 그 후에 열연 스트립은 이 온도에서, 잔류 오스테나이트 양이 5%를 초과하는 강의 베이나이트 변태가 일어나게 하는 데 필요한 유지 시간 동안 유지된다. 펄라이트의 형성은 이 경우에 회피되어야 한다. 필요 한 미세조직을 얻기에 충분한 유지 시간 후에, 제2 냉각 단계의 개시에 의해 변태 공정이 중단되며, 열연 스트립은 400℃ 미만의 온도로 냉각되고 그 후에 350℃ 미만의 권취 온도에서 코일로 권취된다. An alternative method of producing steel strips with polyphase steel has been proposed in EP 1 072 689 B1 (German patent publication DE 600 09 611 T2). According to this known method, first, 0.05% and 0.25% of C (by weight), 0.5% to 3% of Mn, Cu and Ni in total, 0.1% to 4% of total of Si and Al, P, Sn, As and Sb, Ti, Nb, V, Zr and REM in a total amount of less than 0.3%, molten steel containing Cr, Mo and V, remainder Fe and unavoidable impurities each having less than 1% 10 mm, in particular 1 mm to 5 mm. The cast strip is then hot rolled into a hot rolled strip in one or more passes, with a strain ranging from 25% to 70%. The final hot rolling temperature in this case is higher than the Ar 3 temperature. The hot rolled strip obtained at the end of hot rolling is then cooled in two steps. In this first stage of cooling, a cooling rate of 5 ° C to 100 ° C per second is maintained until a temperature in the range of 400 ° C to 550 ° C is reached. The hot-rolled strip is then maintained at this temperature for the holding time necessary to cause bainite transformation of the steel with a residual austenite amount exceeding 5%. The formation of pearlite should be avoided in this case. After a sufficient holding time to obtain the required microstructure, the transformation process is stopped by the start of the second cooling step, and the hot strip is cooled to a temperature of less than 400 DEG C and then wound into coils at a coiling temperature of less than 350 DEG C .
유럽 특허공보 제EP 1 072 689 B1호에 기재된 방법에서는, TRIP 특성["TRIP" = "변태 유기 소성(Transformation Induced Plasticity)"]을 가진 다상 강으로부터 간단한 방법으로 베이나이트 미세조직 분율을 가진 열연 스트립을 제조하는 것이 가능하여야 한다. 그러한 강은 비교적 강도가 높고 성형성이 양호하다. 그러나, 강도는 많은 용도에 있어서, 특히 자동차 구조의 분야에는 충분하지 못하다. In the process described in European Patent Publication No. EP 1 072 689 B1, hot rolled strips having a bainite microstructure fraction in a simple manner from a polyphase steel having TRIP characteristics ["TRIP" = "Transformation Induced Plasticity"] Should be possible. Such steels are relatively strong and formable. However, strength is not sufficient for many applications, particularly in the field of automotive construction.
따라서 본 발명의 목적은 고-인장강도의 평판형 강 제품이 광범위한 형상 치수로 용이하게 제조될 수 있게 하는 방법을 제공하는 것이다. It is therefore an object of the present invention to provide a method by which a plate steel product of high tensile strength can be easily manufactured in a wide range of geometrical dimensions.
이러한 목적은, 전술한 종래 기술에 기초하여, 본 발명에 따라, 다상 미세조직을 형성하고 (중량%로) 0.08% ~ 0.12% C, 1.70% ~ 2.00% Mn, 0.030% 이하의 P(0% 포함), 0.004% 이하의 S(0% 포함), 0.20% 이하의 Si(0% 포함), 0.01% ~ 0.06% Al, 0.0060% 이하의 N(0% 포함), 0.20% ~ 0.50% Cr, 0.010% ~ 0.050% Ti, 0.0010% ~ 0.0045% B 및 잔부 Fe와 불가피한 불순물을 함유하는 강을 두께 1mm ~ 4mm의 주조 스트립으로 주조하고, 주조 스트립을 인-라인(in-line) 연속 공정으로 800℃ 내지 1100℃ 범위의 최종 열연 온도에서 두께 0.5mm 내지 3.2mm의 열연 스트립으로 열연하되, 변형도를 20%보다 크게 하고, 열연 스트립을 250℃ ~ 570℃의 범위의 권취 온도에서 권취하여, 5%의 최소 파단 연신율(A80)에서 최소 인장 강도(Rm)가 800MPa인 열연 스트립을 얻는 평판형 강 제품 제조 방법에 의해 달성된다. According to the present invention, this object is achieved by a method for producing a polyphase microstructure, comprising 0.08% to 0.12% C, 1.70% to 2.00% Mn, 0.030% (Including 0%), 0.20% or less of Si (including 0%), 0.01% to 0.06% Al, 0.0060% or less of N (including 0%), 0.20% to 0.50% 0.010% to 0.050% Ti, 0.0010% to 0.0045% B, and the remainder Fe and unavoidable impurities were cast into a cast strip having a thickness of 1 mm to 4 mm, and the cast strip was subjected to an in-line continuous process at 800 Hot rolled strips having a thickness of 0.5 mm to 3.2 mm at a final hot rolling temperature in the range of from 0 ° C to 1100 ° C and having a deformation degree greater than 20% and winding hot rolled strips at a winding temperature in the range of 250 ° C to 570 ° C, Hot rolled strip having a minimum tensile strength (R m ) of 800 MPa at a minimum fracture elongation (A 80 ) of 10%.
본 발명은 특히 인장강도가 높고 공정 응고할 수 있는 다상 강을 열연 스트립으로 가공하는 스트립 주조의 가능성을 이용한다. 주조 스트립 그 자체는 이 경우에 이미 두께가 작기 때문에, 특히 자동차 구조 분야에 요구되는 바와 같이 얇은 두께의 평판형 제품을 제조하기 위하여, 이러한 스트립의 열연 중에 비교적 낮은 변형도만이 유지되어야 한다. 따라서, 본 발명에 따른 방법으로 주조 스트립의 해당 초기 두께를 규정함으로써, 특성 분포가 최적이고 최대 두께가 1.5mm인 열연 스트립을 어떠한 문제도 없이 제조하는 것이 가능하며, 열연 스트립으로부터 예를 들면 차량의 지지 구조용 구성품이 제조될 수 있다. The present invention takes advantage of the possibility of strip casting, in which poly-phase steels which are high in tensile strength and capable of process coagulation are processed into hot-rolled strips. Since the cast strip itself is already small in this case, only relatively low deformation must be maintained during hot rolling of such strip, in order to produce thin plate products, especially as required in automotive construction applications. Thus, by defining the corresponding initial thickness of the cast strip in accordance with the method according to the invention, it is possible to produce a hot strip with an optimum characteristic distribution and a maximum thickness of 1.5 mm without any problems, Support structural components can be manufactured.
열연 중의 낮은 변형도에 의하여 이에 필요한 압연력은 종래 방법에서의 슬라브 또는 박슬라브의 열연에 필요한 힘에 비하여 낮으므로, 종래 방식으로 주조된 동일한 강도와 두께의 열연 스트립의 폭보다도 실질적으로 큰 광폭의 열연 스트립이 본 발명에 따른 방법으로 아무런 문제도 없이 제조될 수 있다. 따라서 본 발명은, 본 발명에 따라 규정되고 처리되는 조성의 마르텐사이트 강으로 이루어지고 1,200mm보다 큰 폭, 특히 1,600mm보다 큰 폭을 가진 고-인장강도의 열연 스트립이 신뢰적으로 제조될 수 있게 한다. Since the rolling force required by the low deformation degree in hot rolling is lower than the force required for hot rolling the slab or thin slab in the conventional method, the width of the hot rolled strip, which is substantially larger than the width of the hot strip of the same strength and thickness Hot-rolled strips can be produced with no problem in the process according to the invention. The present invention therefore also relates to a process for the production of hot-rolled strips of high-tensile strength with a width greater than 1,200 mm, in particular greater than 1,600 mm, made of martensitic steel of the composition specified and treated in accordance with the invention, do.
본 발명에 따라 구성된 유형의 고-인장강도 강을 가공하기 위한 본 발명에 따른 스트립 주조 공정의 적용은, 전술한 장점 이외에도, 본 방법에 특정된 공정 변수(예를 들면, 열연 최종 온도, 냉각, 권취 온도)와 특성에 의하여, 응고 거동과 관련하여 본 발명에 따라 처리되는 유형의 임계적 강 조성물을 신뢰적으로 주조하는 가능성을 제공한다. 따라서, 스트립 주조의 특징인 주조 스트립의 급속 응고에 의하여, 종래의 제조에 비하여 본 발명에 따라 제조된 열연 스트립은 단면과 길이에 걸쳐서 특성 분포와 미세조직이 특히 균일하므로 중앙 용석(centre liquation)의 발생 위험이 실질적으로 감소한다. The application of the strip casting process according to the present invention for processing high-tensile strength steels of the type configured in accordance with the present invention, in addition to the advantages described above, can also be accomplished by adjusting the process parameters (e.g. hot finish temperature, Coiling temperature) and properties provide the possibility of reliably casting critical steel compositions of the type to be treated in accordance with the invention in connection with the solidification behavior. Therefore, due to the rapid solidification of the cast strip, which is a feature of the strip casting, the hot strip prepared according to the present invention has a characteristic distribution and microstructure particularly uniform over the cross section and the length, The risk of occurrence is substantially reduced.
본 발명에 따른 방법의 다른 특별한 장점에 의하면, 본 발명에 따라 제조된 열연 스트립은, 예를 들면 유럽 특허공보 제EP 1 072 689 B1호에 기재된 열연 종료와 권취 사이에 냉각 중단의 필요에 의하여 유지되어야 하는 열연 스트립의 특별한 냉각 사이클 없이도, 적어도 800MPa의 고강도를 가진다. 본 발명에 따른 방법을 실시함에 있어서, 열연은 비교적 좁은 범위로 국한된 온도 범위(temperature window) 내에서 종료되고 권취는 정밀하게 설정된 온도 범위 내에서 실시되는 것이 확보되어야 할 뿐이다. 그 사이에서는 단일-단계의 냉각이 일어난다. According to another particular advantage of the process according to the invention, the hot-rolled strip produced according to the invention is maintained, for example, by the need for a cooling interruption between the hot rolling finish and the winding described in EP 1 072 689 B1 Even without a special cooling cycle of the hot-rolled strip to be produced. In carrying out the process according to the invention, it is only ensured that the hot rolled steel is finished within a limited temperature window in a relatively narrow range and that the winding is carried out within a precisely set temperature range. In the meantime, single-stage cooling occurs.
본 발명에 따른 방법의 또 다른 장점에 의하면, 하나의 강 분석치(steel analysis)를 기초로 하여, 냉각 및 압연 조건을 변경함으로써, 본 발명에 따라 제조된 스트립의 기계적 물성 범위의 확장이 달성될 수 있다. According to another advantage of the process according to the invention, on the basis of one steel analysis, by changing the cooling and rolling conditions, an expansion of the range of mechanical properties of the strip prepared according to the invention can be achieved have.
본 발명에 따라 제조된 열연 스트립은 냉연 스트립으로의 후속 가공에 특히 적합하다. 따라서, 본 발명의 실용적인 한 실시 형태에서는, 열연 스트립이 자동차 본체 구성에 필요한 두께 0.5mm ~ 1.4mm 특히 0.7mm 내지 1.3mm의 냉연 스트립으로 냉연되는 구성이 제공된다. 냉연 중에 발생하는 경화를 제거하기 위하여, 냉연 스트립은 750℃ ~ 850℃의 소둔 온도에서 소둔될 수 있다. 본 발명에 따라 제조된 열연 스트립으로부터 이와 같이 제조된 냉연 스트립에 대해서는, 800MPa의 최소 인장 강도가 신뢰적으로 보장될 수 있다. 동시에, 냉연 스트립의 최소 파단 연신율(A50)이 10%인 것도 신뢰적으로 보장된다. The hot-rolled strips produced in accordance with the present invention are particularly suitable for subsequent processing into cold-rolled strips. Therefore, in one practical embodiment of the present invention, a configuration is provided in which the hot-rolled strip is cold-rolled into a cold-rolled strip having a thickness of 0.5 mm to 1.4 mm, particularly 0.7 mm to 1.3 mm, necessary for constituting the automobile body. The cold-rolled strip can be annealed at an annealing temperature of 750 ° C to 850 ° C in order to remove the hardening that occurs during cold rolling. With respect to the cold-rolled strip thus produced from the hot-rolled strip produced according to the present invention, the minimum tensile strength of 800 MPa can be reliably ensured. At the same time, it is also reliably ensured that the minimum breaking elongation (A 50 ) of the cold-rolled strip is 10%.
본 발명의 바람직한 다른 실시 형태에 따르면, 냉연 스트립에는 본질적으로 공지된 방식으로 금속 코팅층이 제공되며, 이 경우에 예를 들면 코팅층은 아연 코팅층일 수 있다. According to another preferred embodiment of the invention, the cold-rolled strip is provided with a metallic coating layer in an essentially known manner, for example the coating layer may be a zinc coating layer.
본 발명에 따라 제조된 열연 스트립의 강도와 연신율 값은 해당 최종 열연 온도와 권취 온도의 조정에 의하여 넓은 범위에 결쳐서 조정될 수 있다. 예를 들어, 얻어진 열연 스트립의 최소 파단 연신율(A80)이 10%이고 최소 인장 강도(Rm)가 800MPa인 열연 스트립이 제조되어야 하는 경우에, 이는 900℃ ~ 1000℃의 최종 열연 온도와 420℃ ~ 510℃의 권취 온도에 의하여 달성될 수 있다.The strength and elongation values of the hot-rolled strip produced according to the present invention can be adjusted over a wide range by adjusting the final hot-rolled temperature and coiling temperature. For example, if a hot-rolled strip having a minimum breaking elongation (A 80 ) of 10% and a minimum tensile strength (R m ) of 800 MPa of the obtained hot-rolled strip is to be produced, this means that the final hot- RTI ID = 0.0 > 510 C < / RTI >
한편, 5%의 최소 파단 연신율(A80)에서 적어도 1000MPa의 높은 인장 강도(Rm)가 보장된 연열 스트립이 제조되어야 한다면, 이를 위하여 900℃ 내지 1100℃ 범위의 최종 열연 온도와 450℃ 내지 570℃ 범위의 권취 온도가 선정된다. On the other hand, if a heat-resistant strip having a high tensile strength (R m ) of at least 1000 MPa at a minimum breaking elongation (A 80 ) of 5% is to be produced, it is required to have a final hot rolling temperature in the range of 900 ° C. to 1100 ° C., Lt; 0 > C is selected.
얻어진 열연 스트립의 적어도 1200MPa의 더욱 높은 인장 강도(Rm)와 더불어 5%의 최소 파단 연신율(A80)은 800℃ ~ 1000℃의 최종 열연 온도와 250℃ ~ 550℃의 권취 온도에 의하여 달성될 수 있다.The minimum breaking elongation (A 80 ) of 5% with the higher tensile strength (R m ) of at least 1200 MPa of the hot-rolled strip obtained is achieved by the final hot rolling temperature of 800 ° C to 1000 ° C and the winding temperature of 250 ° C to 550 ° C .
이하에서 예시적인 실시 형태에 기초하여 본 발명을 상세히 설명한다. Hereinafter, the present invention will be described in detail based on exemplary embodiments.
본 발명의 효과를 설명하기 위하여 실시된 시험에서, 본 발명에 따라 표 1에 기재된 조성으로 구성된 2종류의 강 A와 강 B가 용해되고, 일반적인 2-롤(two-roll) 주조기에서 각각 1.6mm 두께의 주조 스트립으로 주조되었다. In a test conducted to explain the effect of the present invention, two types of steel A and steel B constituted by the composition shown in Table 1 were melted in accordance with the present invention, and they were melted in a general two-roll casting machine at 1.6 mm Thick cast strips.
[표 1] (중량%의 데이터)[Table 1] (Data of% by weight)
강 A와 강 B로부터 스트립이 주조된 직후에, 주조 스트립은 인-라인으로 최종 열연 온도(WET)에서 두께 1.25m의 열연 스트립으로 열연되었다. 그 후, 얻어진 각각의 열연 스트립은 바로 냉각 단계에서 권취 온도(HT)까지 냉각되고 권취되었다. 권취 후에, 강 A와 강 B로부터 제조된 각각의 열연 스트립은, 각 경우에 제조 중에 유지된 최종 열연 온도(WET)와 권취 온도(HT)에 따라, 표 2에 기재된 인장 강도(Rm)와 파단 연신율(A80)을 가졌다. Immediately after the strip was cast from steel A and steel B, the cast strip was hot rolled in-line into a hot rolled strip of 1.25 m thick at the final hot rolling temperature (WET). Each hot-rolled strip obtained was then cooled and rolled up to the coiling temperature HT in the immediately cooling step. After winding, each hot-rolled strip produced from the steel A and the steel B has tensile strength (R m ) shown in Table 2 and tensile strength R m shown in Table 2 according to the final hot rolling temperature (WET) and the coiling temperature And a fracture elongation (A 80 ).
[표 2][Table 2]
시험 4에 따라 강 B로부터 제조된 열연 스트립은 권취와 산세 후에 0.7mm 두께의 냉연 스트립으로 냉연되었고, 스트립의 재결정을 위하여 인-라인으로 800℃의 온도에서 소둔되었다. The hot-rolled strips produced from steel B according to test 4 were cold rolled into cold-rolled strips of 0.7 mm thickness after winding and pickling and annealed in-line at a temperature of 800 ° C for recrystallization of the strips.
이와 같이 얻어진 냉연 스트립은 파단 연신율(A50)이 11.5%이고 인장 강도(Rm)가 835MPa이었다.The cold-rolled strip thus obtained had an elongation at break (A 50 ) of 11.5% and a tensile strength (R m ) of 835 MPa.
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| EP06123139A EP1918406B1 (en) | 2006-10-30 | 2006-10-30 | Process for manufacturing steel flat products from boron microalloyed multi phase steel |
| EP06123139.5 | 2006-10-30 | ||
| PCT/EP2007/061390 WO2008052919A1 (en) | 2006-10-30 | 2007-10-24 | Method for manufacturing flat steel products from a multiphase steel microalloyed with boron |
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Families Citing this family (16)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US10071416B2 (en) * | 2005-10-20 | 2018-09-11 | Nucor Corporation | High strength thin cast strip product and method for making the same |
| EP2209926B1 (en) | 2007-10-10 | 2019-08-07 | Nucor Corporation | Complex metallographic structured steel and method of manufacturing same |
| US20110277886A1 (en) | 2010-02-20 | 2011-11-17 | Nucor Corporation | Nitriding of niobium steel and product made thereby |
| DE102011117572A1 (en) * | 2011-01-26 | 2012-08-16 | Salzgitter Flachstahl Gmbh | High-strength multiphase steel with excellent forming properties |
| EP2489748B1 (en) * | 2011-02-18 | 2017-12-13 | ThyssenKrupp Steel Europe AG | Hot-rolled steel surface product produced from a complex phase steel and method for the manufacture |
| WO2013182622A1 (en) * | 2012-06-05 | 2013-12-12 | Thyssenkrupp Steel Europe Ag | Steel, sheet steel product and process for producing a sheet steel product |
| CN102766821B (en) * | 2012-07-31 | 2014-10-29 | 宝山钢铁股份有限公司 | High-strength thick steel plate for large heat input welding |
| JP5942712B2 (en) * | 2012-09-06 | 2016-06-29 | 新日鐵住金株式会社 | Scum weir, thin slab manufacturing method, thin slab manufacturing equipment |
| AT512399B1 (en) * | 2012-09-10 | 2013-08-15 | Siemens Vai Metals Tech Gmbh | Method for producing a microalloyed tubular steel in a cast-rolled composite plant and microalloyed tubular steel |
| EP2759614B1 (en) | 2013-01-25 | 2019-01-02 | ThyssenKrupp Steel Europe AG | Method for generating a flat steel product with an amorphous, semi-amorphous or fine crystalline structure and flat steel product with such structures |
| DE102013013067A1 (en) | 2013-07-30 | 2015-02-05 | Salzgitter Flachstahl Gmbh | Silicon-containing microalloyed high-strength multiphase steel having a minimum tensile strength of 750 MPa and improved properties and processes for producing a strip of this steel |
| EP2924141B1 (en) * | 2014-03-25 | 2017-11-15 | ThyssenKrupp Steel Europe AG | Cold rolled steel flat product and method for its production |
| CN105950984B (en) * | 2016-05-06 | 2018-03-27 | 武汉钢铁有限公司 | Tensile strength 650MPa level hot rolling Multiphase Steels and its production method |
| DE102017209982A1 (en) * | 2017-06-13 | 2018-12-13 | Thyssenkrupp Ag | High strength steel sheet with improved formability |
| CN113481436A (en) * | 2021-06-29 | 2021-10-08 | 鞍钢股份有限公司 | 800 MPa-grade hot-rolled complex phase steel and production method thereof |
| CN113584270B (en) * | 2021-08-09 | 2023-03-24 | 新疆八一钢铁股份有限公司 | Process for improving processability of steel for barrel industry |
Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2005095664A1 (en) * | 2004-03-31 | 2005-10-13 | Jfe Steel Corporation | High-rigidity high-strength thin steel sheet and method for producing same |
Family Cites Families (16)
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| US5470529A (en) * | 1994-03-08 | 1995-11-28 | Sumitomo Metal Industries, Ltd. | High tensile strength steel sheet having improved formability |
| ATE278811T1 (en) * | 1996-07-12 | 2004-10-15 | Thyssenkrupp Stahl Ag | HOT STEEL STRIP AND METHOD FOR PRODUCING IT |
| DE19710125A1 (en) * | 1997-03-13 | 1998-09-17 | Krupp Ag Hoesch Krupp | Process for the production of a steel strip with high strength and good formability |
| FR2796966B1 (en) * | 1999-07-30 | 2001-09-21 | Ugine Sa | PROCESS FOR THE MANUFACTURE OF THIN STRIP OF TRIP-TYPE STEEL AND THIN STRIP THUS OBTAINED |
| FR2798871B1 (en) * | 1999-09-24 | 2001-11-02 | Usinor | PROCESS FOR PRODUCING CARBON STEEL STRIPS, ESPECIALLY STEEL FOR PACKAGING, AND STRIPS THUS PRODUCED |
| EP1170390A4 (en) * | 1999-09-28 | 2005-02-23 | Jfe Steel Corp | Hot-rolled steel sheet having high tensile strength and method for production thereof |
| WO2001062997A1 (en) * | 2000-02-23 | 2001-08-30 | Kawasaki Steel Corporation | High tensile hot-rolled steel sheet having excellent strain aging hardening properties and method for producing the same |
| AUPQ779900A0 (en) * | 2000-05-26 | 2000-06-22 | Bhp Steel (Jla) Pty Limited | Hot rolling thin strip |
| EP1327697A4 (en) * | 2000-10-19 | 2009-11-11 | Jfe Steel Corp | Zinc-plated steel sheet and method for preparation thereof, and method for manufacturing formed article by press working |
| DE10062919A1 (en) * | 2000-12-16 | 2002-06-27 | Thyssenkrupp Stahl Ag | Process for producing hot strip or sheet from a microalloyed steel |
| DE10128544C2 (en) * | 2001-06-13 | 2003-06-05 | Thyssenkrupp Stahl Ag | High-strength, cold-workable sheet steel, process for its production and use of such a sheet |
| DE10161465C1 (en) * | 2001-12-13 | 2003-02-13 | Thyssenkrupp Stahl Ag | Production of hot strip used in vehicle chassis comprises casting steel into pre-material, hot rolling to form hot strip, cooling in first cooling step, and cooling in second cooling step after pause to coiling temperature |
| US6878920B2 (en) * | 2002-06-28 | 2005-04-12 | Intel Corporation | Optical receiver circuit, method, and system |
| EP1396550A1 (en) * | 2002-08-28 | 2004-03-10 | ThyssenKrupp Stahl AG | Method for manufacturing hot strip |
| JP4510488B2 (en) * | 2004-03-11 | 2010-07-21 | 新日本製鐵株式会社 | Hot-dip galvanized composite high-strength steel sheet excellent in formability and hole expansibility and method for producing the same |
| CN100447280C (en) * | 2005-10-10 | 2008-12-31 | 燕山大学 | Impact stage low carbon steel hot-rolled sheet and mfg. method thereof |
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- 2007-10-24 KR KR1020097007485A patent/KR101461583B1/en active IP Right Grant
- 2007-10-24 WO PCT/EP2007/061390 patent/WO2008052919A1/en active Application Filing
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| Publication number | Priority date | Publication date | Assignee | Title |
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| WO2005095664A1 (en) * | 2004-03-31 | 2005-10-13 | Jfe Steel Corporation | High-rigidity high-strength thin steel sheet and method for producing same |
Also Published As
| Publication number | Publication date |
|---|---|
| WO2008052919A1 (en) | 2008-05-08 |
| CN101528970B (en) | 2012-10-03 |
| ATE432376T1 (en) | 2009-06-15 |
| PL1918406T3 (en) | 2009-10-30 |
| DE502006003835D1 (en) | 2009-07-09 |
| US20100043513A1 (en) | 2010-02-25 |
| CN101528970A (en) | 2009-09-09 |
| JP5350253B2 (en) | 2013-11-27 |
| EP1918406A1 (en) | 2008-05-07 |
| KR20090084815A (en) | 2009-08-05 |
| EP1918406B1 (en) | 2009-05-27 |
| ES2325962T3 (en) | 2009-09-25 |
| JP2010508435A (en) | 2010-03-18 |
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