EP2665837A1 - Method to produce a hot formed part, and part thus formed - Google Patents
Method to produce a hot formed part, and part thus formedInfo
- Publication number
- EP2665837A1 EP2665837A1 EP12700452.1A EP12700452A EP2665837A1 EP 2665837 A1 EP2665837 A1 EP 2665837A1 EP 12700452 A EP12700452 A EP 12700452A EP 2665837 A1 EP2665837 A1 EP 2665837A1
- Authority
- EP
- European Patent Office
- Prior art keywords
- blank
- hot forming
- temperature
- forming press
- heated
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Ceased
Links
Classifications
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
- B21J—FORGING; HAMMERING; PRESSING METAL; RIVETING; FORGE FURNACES
- B21J1/00—Preparing metal stock or similar ancillary operations prior, during or post forging, e.g. heating or cooling
- B21J1/06—Heating or cooling methods or arrangements specially adapted for performing forging or pressing operations
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
- B21J—FORGING; HAMMERING; PRESSING METAL; RIVETING; FORGE FURNACES
- B21J3/00—Lubricating during forging or pressing
-
- 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
- C21D1/00—General methods or devices for heat treatment, e.g. annealing, hardening, quenching or tempering
- C21D1/02—Hardening articles or materials formed by forging or rolling, with no further heating beyond that required for the formation
-
- 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
- C21D8/005—Modifying the physical properties by deformation combined with, or followed by, heat treatment of ferrous alloys
Definitions
- the invention relates to a method for manufacturing a coated steel part having very high mechanical properties using hot forming techniques, and a part thus formed.
- Hot forming of parts is well-known in the art and is used in the automotive industry to produce complex parts with a reduced weight.
- the heated blank has a temperature of at most 780° C when placed in the hot forming press.
- micro-cracks is strongly influenced by the temperature of the blank when it is placed in the hot forming press and the temperature at which the hot formed part is formed in the hot forming press.
- high temperatures such as used in the art, many micro-cracks are formed in the substrate, which often have a depth of more than 10 ⁇ .
- Lowering the temperature at which the coated blank is placed in the hot forming press reduced the micro-cracks in number and depth. It has been found that cooling the heated blank to a temperature of at most 780° C when placed in the hot forming press already reduces the number and depth of the micro-cracks to a considerable extent.
- the blank is heated to a temperature of 850° C or more, more preferably a temperature of 880° C or more, and still more preferably to a temperature of 900° C or more.
- the coated blank is heated to a temperature such that the substrate is fully and homogenously austenitised before it is placed in the hot forming press.
- the heated blank has a temperature of at least 500° C when placed in the hot forming press, more preferably a temperature of at least 600° C, and still more preferably a temperature of at least 650° C.
- the temperature of the blank can be below the Arl temperature when placed into the blank, but preferably the blank is not cooled too far because the cooling rate is very critical at low temperatures.
- the heated blank has a temperature of at most 740° C when placed in the hot forming press, and more preferably a temperature of at most 700° C.
- the temperature of the blank should be as low as possible to prevent (large) micro-cracks. Thus, it is optimal if the temperature of the blank is between 650° C and 700° C when the blank is placed in the hot forming press.
- the heated blank is at least partially cooled between the furnace and the hot forming press by forced cooling, preferably with an average cooling velocity of at least 30° C/sec, more preferably with an average cooling velocity of at least 40° C/sec, still more preferably with an average cooling velocity of at least 60° C/sec, most preferably with an average cooling velocity of at least 80° C/sec.
- Forced cooling effectively reduces the blank temperature at a cooling rate that is higher than the cooling rate obtainable when the blank is cooled in open air.
- a high cooling velocity is preferred, so the time in which the blank is kept between the furnace and the hot forming press can be as short as possible. This is advantageous so as to realise desired high strength of the formed part and so as to reduce oxidation of the coating on the blank.
- the heated steel blank is transported between the furnace and the hot forming press in a time span of at most 10 seconds, more preferably in a time span of at most 8 seconds, and still more preferably in a time span of at most 6 seconds.
- a short transportation time is also advantageous to reduce the cycle time to produce a hot formed part.
- the heated blank is cooled between the furnace and the hot forming press using accelerated cooling making use of gas, such as cooling with forced air flow, cooling with forced N 2 flow, or cooling with forced C0 2 flow or cooled C0 2 using solid C0 2.
- gas such as cooling with forced air flow, cooling with forced N 2 flow, or cooling with forced C0 2 flow or cooled C0 2 using solid C0 2.
- the heated blank is cooled between the furnace and the hot forming press using liquid or solid material, such as liquid or solid C0 2 particles or metal cooling plates.
- liquid or solid material such as liquid or solid C0 2 particles or metal cooling plates.
- Liquid or solid material will provide a fast cooling rate, but is more difficult to control.
- Solid C0 2 particles for instance have the advantage of a fast cooling capacity and the additional advantage that oxide layers on the coating are at least partially removed at the same time, but solid C0 2 particles are more difficult to supply at the right time period.
- Metal cooling plates that are brought into contact with the heated blank provide a very fast cooling rate, but a tight control of the cooling time is required.
- the coating on the blank is a metallic coating, preferably a coating layer of zinc or a zinc alloy.
- Zinc or zinc alloy can provide an active corrosion protection.
- the zinc alloy consists of 0.3 - 4.0% Mg and 0.05 - 6.0% Al, optionally at most 0.2% of one or more additional elements, unavoidable impurities, the remainder being zinc. It has been found that such a zinc alloy provides a better corrosion resistance to the hot formed part.
- the zinc or zinc alloy layer is pre-diffused in the substrate.
- the pre-diffused coating makes it possible to heat the blank fast to a temperature above the Ac3 temperature.
- the zinc or zinc alloy coated steel blank contains an average of 10 - 75 % iron in the coating after heating the blank in the furnace, preferably an average of 25 - 55 %.
- This amount of iron in the coating ensures that the (initial) zinc or zinc alloy coating does not evaporate at temperatures above the Ac3 temperature.
- the hot forming press is internally cooled such that the blank is cooled with a cooling velocity of at least 50° C/sec during the first second after the press is fully closed, preferably with a cooling velocity of at least 100° C/sec during the first second.
- This very fast cooling rate after the hot forming press is fully closed makes that the austenitic structure of the heated blank is transformed fully or almost fully to a martensitic structure.
- the hot forming press is fully closed in at most one second. This fast closing of the hot forming press is advantageous so as to fast cool also the portions of the blank that are not in immediate contact with the press.
- a hot formed part manufactured according to the above method, wherein the substrate of the part is free of micro-cracks having a depth of more than 15 ⁇ , and preferably the substrate is free of micro-cracks having a depth of more than 10 ⁇ . Parts having less deep micro-cracks are preferred over parts having deeper micro-cracks.
- a hot formed part manufactured according to the above method, wherein the micro-cracks in the substrate have an average depth of at most 3 ⁇ in five surface area's of the blank with a size of 1 cm 2 . Parts having on average shallow micro-cracks are preferred over parts having deep micro-cracks on average.
Landscapes
- Engineering & Computer Science (AREA)
- Chemical & Material Sciences (AREA)
- Mechanical Engineering (AREA)
- Physics & Mathematics (AREA)
- Thermal Sciences (AREA)
- Crystallography & Structural Chemistry (AREA)
- Materials Engineering (AREA)
- Metallurgy (AREA)
- Organic Chemistry (AREA)
- Heat Treatment Of Articles (AREA)
- Shaping Metal By Deep-Drawing, Or The Like (AREA)
Abstract
Description
Claims
Priority Applications (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
EP14163594.6A EP2754723A3 (en) | 2011-01-17 | 2012-01-17 | Method to produce a hot formed part, and part thus formed |
EP12700452.1A EP2665837A1 (en) | 2011-01-17 | 2012-01-17 | Method to produce a hot formed part, and part thus formed |
Applications Claiming Priority (3)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
EP11000315 | 2011-01-17 | ||
PCT/EP2012/000186 WO2012097976A1 (en) | 2011-01-17 | 2012-01-17 | Method to produce a hot formed part, and part thus formed |
EP12700452.1A EP2665837A1 (en) | 2011-01-17 | 2012-01-17 | Method to produce a hot formed part, and part thus formed |
Related Child Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
EP14163594.6A Division EP2754723A3 (en) | 2011-01-17 | 2012-01-17 | Method to produce a hot formed part, and part thus formed |
Publications (1)
Publication Number | Publication Date |
---|---|
EP2665837A1 true EP2665837A1 (en) | 2013-11-27 |
Family
ID=44003816
Family Applications (2)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
EP12700452.1A Ceased EP2665837A1 (en) | 2011-01-17 | 2012-01-17 | Method to produce a hot formed part, and part thus formed |
EP14163594.6A Ceased EP2754723A3 (en) | 2011-01-17 | 2012-01-17 | Method to produce a hot formed part, and part thus formed |
Family Applications After (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
EP14163594.6A Ceased EP2754723A3 (en) | 2011-01-17 | 2012-01-17 | Method to produce a hot formed part, and part thus formed |
Country Status (3)
Country | Link |
---|---|
EP (2) | EP2665837A1 (en) |
CN (1) | CN103403195B (en) |
WO (1) | WO2012097976A1 (en) |
Families Citing this family (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
GB201116668D0 (en) * | 2011-09-27 | 2011-11-09 | Imp Innovations Ltd | A method of forming parts from sheet steel |
CN106715745A (en) * | 2014-03-28 | 2017-05-24 | 塔塔钢铁艾默伊登有限责任公司 | Method for hot forming a coated steel blank |
JP6152836B2 (en) * | 2014-09-25 | 2017-06-28 | Jfeスチール株式会社 | Manufacturing method of hot press-formed product |
DE102014114394B3 (en) * | 2014-10-02 | 2015-11-05 | Voestalpine Stahl Gmbh | Method for producing a hardened steel sheet |
DE102015001408A1 (en) * | 2015-02-06 | 2016-08-11 | Eisenmann Se | Plant for the form hardening of workpieces |
Citations (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
WO2006015849A2 (en) | 2004-08-09 | 2006-02-16 | Voestalpine Automotive Holding Gmbh | Method for press quenching components consisting of sheet steel |
DE102006019395A1 (en) | 2006-04-24 | 2007-10-25 | Thyssenkrupp Steel Ag | Apparatus and method for forming blanks of higher and highest strength steels |
DE102008039264A1 (en) | 2008-08-22 | 2010-03-04 | Schuler Cartec Gmbh & Co. Kg | Method for tempering with intermediate cooling |
EP2324938A1 (en) | 2009-10-23 | 2011-05-25 | ThyssenKrupp Umformtechnik GmbH | Method and thermal recasting assembly for producing a hardened, thermally recast workpiece |
EP2623226A1 (en) | 2010-09-30 | 2013-08-07 | Kabushiki Kaisha Kobe Seiko Sho | Press-molded article and method for producing same |
Family Cites Families (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JP4506128B2 (en) * | 2003-08-29 | 2010-07-21 | 住友金属工業株式会社 | Hot press-formed product and method for producing the same |
DE102004006093B3 (en) | 2004-02-06 | 2005-12-01 | Fes Gmbh Fahrzeug-Entwicklung Sachsen | Method for producing a three-dimensionally shaped armor component for vehicle bodies |
DE102005003551B4 (en) | 2005-01-26 | 2015-01-22 | Volkswagen Ag | Method for hot forming and hardening a steel sheet |
JP4733522B2 (en) | 2006-01-06 | 2011-07-27 | 新日本製鐵株式会社 | Method for producing high-strength quenched molded body with excellent corrosion resistance and fatigue resistance |
JP4825882B2 (en) * | 2009-02-03 | 2011-11-30 | トヨタ自動車株式会社 | High-strength quenched molded body and method for producing the same |
-
2012
- 2012-01-17 EP EP12700452.1A patent/EP2665837A1/en not_active Ceased
- 2012-01-17 CN CN201280005548.4A patent/CN103403195B/en active Active
- 2012-01-17 EP EP14163594.6A patent/EP2754723A3/en not_active Ceased
- 2012-01-17 WO PCT/EP2012/000186 patent/WO2012097976A1/en active Application Filing
Patent Citations (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
WO2006015849A2 (en) | 2004-08-09 | 2006-02-16 | Voestalpine Automotive Holding Gmbh | Method for press quenching components consisting of sheet steel |
DE102006019395A1 (en) | 2006-04-24 | 2007-10-25 | Thyssenkrupp Steel Ag | Apparatus and method for forming blanks of higher and highest strength steels |
DE102008039264A1 (en) | 2008-08-22 | 2010-03-04 | Schuler Cartec Gmbh & Co. Kg | Method for tempering with intermediate cooling |
EP2324938A1 (en) | 2009-10-23 | 2011-05-25 | ThyssenKrupp Umformtechnik GmbH | Method and thermal recasting assembly for producing a hardened, thermally recast workpiece |
EP2623226A1 (en) | 2010-09-30 | 2013-08-07 | Kabushiki Kaisha Kobe Seiko Sho | Press-molded article and method for producing same |
Non-Patent Citations (2)
Title |
---|
H. KARBASIAN ET AL: "A review on hot stamping", JOURNAL OF MATERIALS PROCESSING TECHNOLOGY, vol. 210, no. 15, 1 November 2010 (2010-11-01), pages 2103 - 2118, XP055141086, ISSN: 0924-0136, DOI: 10.1016/j.jmatprotec.2010.07.019 * |
See also references of WO2012097976A1 * |
Also Published As
Publication number | Publication date |
---|---|
WO2012097976A1 (en) | 2012-07-26 |
EP2754723A3 (en) | 2016-08-31 |
CN103403195B (en) | 2016-05-04 |
EP2754723A2 (en) | 2014-07-16 |
CN103403195A (en) | 2013-11-20 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
US20180340266A1 (en) | Method for Manufacturing a Product from a Flexibly Rolled Strip Material | |
JP5727037B2 (en) | Method for producing a cured structural element | |
DE502006006289D1 (en) | METHOD FOR THE MELT EXTRACTION TEMPERATURE OF A STEEL FLAT PRODUCT OF HIGH-TIGHT STEEL | |
US9127329B2 (en) | Method for hot forming a coated metal part and formed part | |
WO2012097976A1 (en) | Method to produce a hot formed part, and part thus formed | |
CN102257166A (en) | Method for manufacturing a coated part using hot forming techniques | |
RU2013114861A (en) | METHOD FOR PRODUCING PRODUCTS FROM TEXTURED ELECTRICAL STEEL WITH HIGH DENSITY OF MAGNETIC FLOW | |
JP2007182608A (en) | Method for manufacturing high-strength formed and quenched body superior in corrosion resistance and fatigue resistance, and manufacturing facility therefor | |
BR112017007273B1 (en) | cold rolled and annealed, recrystallized flat steel product and method for manufacturing a formed flat steel product | |
CN101932747A (en) | Method for producing a component from a steel product provided with an al-si coating and intermediate product of such a method | |
US20150027596A1 (en) | Steel sheet for hot press-forming, method for manufacturing the same, and method for producing hot press-formed parts using the same | |
CN102781601A (en) | Hot press forming process of plated steel and hot press formed articles using the same | |
JPWO2008153183A1 (en) | Manufacturing method of molded products | |
JP6356808B2 (en) | Annealing method of steel sheet | |
JP2017500451A5 (en) | ||
EP3088549B1 (en) | Steel sheet for hot forming and manufacturing method of hot press formed steel member | |
JP2011117086A (en) | High-strength hardened body having excellent corrosion resistance and fatigue resistance | |
JP2016502590A5 (en) | ||
US9744744B2 (en) | Press-formed article and method for manufacturing same | |
CN108431286B (en) | Hot press molded article with suppressed microcrack and process for producing the same | |
KR20200087817A (en) | Method for pre-oxidation of strip steel in a reaction chamber placed in a furnace chamber | |
JP2011184797A (en) | High strength hardened molded body having excellent corrosion resistance and fatigue resistance | |
CN107746912A (en) | Metalwork anti-deformation Technology for Heating Processing | |
TH171935B (en) | Manufacturing method of high strength hot dip galvanized steel sheet and plated steel sheet. Hot dipped galvanized and made into high strength alloy. | |
TH112638A (en) |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
PUAI | Public reference made under article 153(3) epc to a published international application that has entered the european phase |
Free format text: ORIGINAL CODE: 0009012 |
|
17P | Request for examination filed |
Effective date: 20130819 |
|
AK | Designated contracting states |
Kind code of ref document: A1 Designated state(s): AL AT BE BG CH CY CZ DE DK EE ES FI FR GB GR HR HU IE IS IT LI LT LU LV MC MK MT NL NO PL PT RO RS SE SI SK SM TR |
|
DAX | Request for extension of the european patent (deleted) | ||
TPAC | Observations filed by third parties |
Free format text: ORIGINAL CODE: EPIDOSNTIPA |
|
17Q | First examination report despatched |
Effective date: 20150210 |
|
APBK | Appeal reference recorded |
Free format text: ORIGINAL CODE: EPIDOSNREFNE |
|
APBN | Date of receipt of notice of appeal recorded |
Free format text: ORIGINAL CODE: EPIDOSNNOA2E |
|
APAF | Appeal reference modified |
Free format text: ORIGINAL CODE: EPIDOSCREFNE |
|
REG | Reference to a national code |
Ref country code: DE Ref legal event code: R003 |
|
APBT | Appeal procedure closed |
Free format text: ORIGINAL CODE: EPIDOSNNOA9E |
|
STAA | Information on the status of an ep patent application or granted ep patent |
Free format text: STATUS: THE APPLICATION HAS BEEN REFUSED |
|
18R | Application refused |
Effective date: 20170127 |