WO2013006108A1 - A method of hot-shaping and hardening a sheet steel blank - Google Patents
A method of hot-shaping and hardening a sheet steel blank Download PDFInfo
- Publication number
- WO2013006108A1 WO2013006108A1 PCT/SE2012/000104 SE2012000104W WO2013006108A1 WO 2013006108 A1 WO2013006108 A1 WO 2013006108A1 SE 2012000104 W SE2012000104 W SE 2012000104W WO 2013006108 A1 WO2013006108 A1 WO 2013006108A1
- Authority
- WO
- WIPO (PCT)
- Prior art keywords
- temperature
- product
- tool pair
- formation
- bainite
- 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
-
- 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
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
- B21D—WORKING OR PROCESSING OF SHEET METAL OR METAL TUBES, RODS OR PROFILES WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
- B21D22/00—Shaping without cutting, by stamping, spinning, or deep-drawing
- B21D22/02—Stamping using rigid devices or tools
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
- B21D—WORKING OR PROCESSING OF SHEET METAL OR METAL TUBES, RODS OR PROFILES WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
- B21D22/00—Shaping without cutting, by stamping, spinning, or deep-drawing
- B21D22/02—Stamping using rigid devices or tools
- B21D22/022—Stamping using rigid devices or tools by heating the blank or stamping associated with heat treatment
-
- 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
- C21D1/18—Hardening; Quenching with or without subsequent tempering
- C21D1/19—Hardening; Quenching with or without subsequent tempering by interrupted quenching
- C21D1/20—Isothermal quenching, e.g. bainitic hardening
-
- 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
- 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
-
- 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
-
- 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
- C21D9/0068—Heat treatment, e.g. annealing, hardening, quenching or tempering, adapted for particular articles; Furnaces therefor for particular articles not mentioned below
-
- 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
- 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
- C21D2211/002—Bainite
Definitions
- the invention relates to a method of hot forming and hardening a sheet steel blankby forming the material heated to the austenite range in a tool pair that rapidly cools the shaped product.
- a steel with bainite structure can have approximately the same high tensile strengthas the one obtained with the press-hardening process but the bainite structure is tougher and more ductile than the martensitic structure.
- US 6,149,743 describes a method for bainite hardening. The material is rapidly cooled from the austenite range to just above Ms (the temperature for the start of the formation of martensite) and this temperature is maintained for approximately 10 hours and, toward the end of theholding time, the temperature is raised in order to shorten the hardening time. This process can be used for roller bearings.
- the formed product is rapidly cooled until the product's temperature drops below the temperature for the start of the formation of martensite and the product's temperature 5is then raised until it exceeds the temperature for the start of the formation of martensite and is maintained there until bainite is formed.
- the times and the temperatures for the formation of martensite and the formation of bainite can be selected so that the material comes to contain more than 50% by volume bainite.
- the forming and the rapid cooling take a few seconds while maintaining the heat takes a few lOminutes.
- the time for maintaining the heat (the holding time) can be utilized for subsequent working, e.g. edge cutting.
- Figure 1 is a time-temperature diagram for an example of a process in accordance 15with the invention.
- FIG. 2 is a block diagram that shows the process.
- Figure 2 shows a block diagram with an austenitic phase in a furnace 11 , a forming 20phase in a cooled forming tool 12, and a subsequent temperature holding in a furnace 13.
- the temperature curve in figure 1 for an example of a process in accordance with the invention shows a first part 20 that is the heating in a furnace of a blank to the aus-
- the moving of the material to a cooled forming tool pair normally takes 5-10 seconds and entails a small reduction of temperature.
- the forming in the cold tool pair is in the order of magnitude of one or a few seconds but the product must remain in the tools until it is rapidly cooled to somewhat below Ms (the temperature for the start of a formation of martensite).
- 30formation of martensite is instantaneous and is a function of the temperature but is not a function of the time.
- This cooling is accordingly carried out with the tool pair as fixture.
- the forming and rapid cooling is designated as 22.
- the product is rapidly taken out of the tool pair and the started formation of martensite generates heat and entails an elevation of temperature 23 that may exceed Ms. Additional heat can be used, e.g., induction heat or radiant heat in order to rapidly bring the temperature up above Ms.
- the product is then moved to a furnace where the product is maintainedat a rather even temperature somewhat above Ms for a number of minutes represented by the curve part 24.
- the product is thereafter cooled down in the air, which is represented by the dashed curve part 25 or is speeded up as is represented by the curve part 26.
- the start of formation of martensite favours the formation of bainite and the holding time for the formation of bainite is shortened, generally to less than half an hour or below 10 minutes or even below 1 min. This is a prerequisite for an economical process
- the amount of martensite can be predetermined by selecting how much the temperature is lowered below Ms.
- the temperature for the formation of bainite canbe made to vary by a few tens of degrees and therefore the holding time can be used for subsequent working, e.g.
- edge cutting which is advantageous to carry out before the material reaches its full hardness, since this reduces the wear on the tool and also reduces the risk for the initiation of fissures and the following formation of fissures when the product is used.
- the subsequent working can also be integrated intothe shaping tool and be integrated in the curve part 22, i.e. it can be carried out before or during the formation of martensite.
- the product can be formed in a first tool pair and cooled down to just over Ms and the formed product can then be moved to a second tool pair thatmakes the fixture and cools the product down to somewhat below Ms.
- This second tool pair can carry out the subsequent work at the same time, e.g. edge cutting, before the product is moved to the furnace for maintaining the heat.
- the subsequent working can be integrated in the first tool pair.
- the two tool pairs can work simultaneously, which shortens the cycle time.
- Boron steel is used in conventional press hardening, that is, a carbon-manganese steel with boron, that completely hardens to martensite.
- a carbon-silicon-manganese steel can be suitably used in a process in accordance with the invention.
- the steel can have a carbon content of 0.2-0.3 weight %, a manganese content of 1-2 weight % and a silicon content of 1-2 weight %.
- chromium and other customary alloy substances with a total content less than 1 weight % may be present. Siliconprevents the separation of cementite and creates the desired microstructure.
Landscapes
- 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)
- Heat Treatment Of Articles (AREA)
Abstract
Description
Claims
Priority Applications (5)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2014518485A JP2014524979A (en) | 2011-07-06 | 2012-07-04 | Method of thermoforming and quenching steel sheet blanks |
| US13/261,782 US20150090378A1 (en) | 2011-07-06 | 2012-07-04 | Method of hot-shaping and hardening a sheet steel blank |
| EP12808151.0A EP2729587A4 (en) | 2011-07-06 | 2012-07-04 | METHOD FOR HOT SHAPING AND CURING A FLAN OF STEEL SHEET |
| KR1020147003040A KR20140051934A (en) | 2011-07-06 | 2012-07-04 | A method of hot shaping and hardening a sheet steel blank |
| CN201280027136.0A CN103582707A (en) | 2011-07-06 | 2012-07-04 | A method of hot-shaping and hardening a sheet steel blank |
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| SE1100523A SE1100523A1 (en) | 2011-07-06 | 2011-07-06 | Ways to heat mold and harden a sheet metal blank |
| SE1100523-8 | 2011-07-06 |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| WO2013006108A1 true WO2013006108A1 (en) | 2013-01-10 |
Family
ID=47436353
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| PCT/SE2012/000104 Ceased WO2013006108A1 (en) | 2011-07-06 | 2012-07-04 | A method of hot-shaping and hardening a sheet steel blank |
Country Status (7)
| Country | Link |
|---|---|
| US (1) | US20150090378A1 (en) |
| EP (1) | EP2729587A4 (en) |
| JP (1) | JP2014524979A (en) |
| KR (1) | KR20140051934A (en) |
| CN (1) | CN103582707A (en) |
| SE (1) | SE1100523A1 (en) |
| WO (1) | WO2013006108A1 (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP3548641B1 (en) | 2016-11-29 | 2020-08-26 | Tata Steel IJmuiden B.V. | Method for manufacturing a hot-formed article, and obtained article |
Families Citing this family (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE102014016614A1 (en) * | 2014-10-31 | 2016-05-04 | Salzgitter Flachstahl Gmbh | Process for producing a component by forming a steel circuit board |
| EP3327152B1 (en) * | 2016-11-29 | 2023-10-11 | Tata Steel UK Limited | Method for hot-forming a steel blank |
| WO2018174082A1 (en) | 2017-03-24 | 2018-09-27 | 新日鐵住金株式会社 | Hat member and manufacturing method therefor |
| US11283395B2 (en) | 2018-03-23 | 2022-03-22 | Nextracker Inc. | Multiple actuator system for solar tracker |
| US11387771B2 (en) | 2018-06-07 | 2022-07-12 | Nextracker Llc | Helical actuator system for solar tracker |
| US11050383B2 (en) | 2019-05-21 | 2021-06-29 | Nextracker Inc | Radial cam helix with 0 degree stow for solar tracker |
Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO1999002744A1 (en) * | 1997-07-10 | 1999-01-21 | Skf Engineering & Research Centre B.V. | Method for performing a heat treatment on metallic rings, and bearing ring thus obtained |
| WO2004022794A1 (en) * | 2002-09-04 | 2004-03-18 | Colorado School Of Mines | Method for producing steel with retained austenite |
| JP2005177805A (en) * | 2003-12-19 | 2005-07-07 | Nippon Steel Corp | Hot press molding method |
| US20100139821A1 (en) * | 2008-10-16 | 2010-06-10 | Hubertus Giefers | Method for producing a workpiece, a workpiece and use of a workpiece |
| WO2010150683A1 (en) * | 2009-06-22 | 2010-12-29 | 新日本製鐵株式会社 | Hot press-forming method for steel sheets, hot press-forming device for steel sheets, and steel formed member |
Family Cites Families (11)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US3337376A (en) * | 1966-12-27 | 1967-08-22 | United States Steel Corp | Method of hardening hypereutectoid steels |
| JPS5235756A (en) * | 1975-09-16 | 1977-03-18 | Honda Motor Co Ltd | Method of making brake disc |
| JPH02153019A (en) * | 1988-12-06 | 1990-06-12 | Mazda Motor Corp | Production of steel member |
| JPH09296214A (en) * | 1996-04-29 | 1997-11-18 | Aisin Seiki Co Ltd | Solid forming austemper processing method and apparatus |
| SE510344C2 (en) * | 1997-08-01 | 1999-05-17 | Ovako Steel Ab | Way for complete bainite hardening of steel |
| FR2839727B1 (en) * | 2002-05-14 | 2004-06-25 | Technologica Sarl | PROCESS FOR THE PREPARATION AND SHAPING OF CAST IRON PARTS WITH SPHEROIDAL GRAPHITE WITH HIGH MECHANICAL CHARACTERISTICS |
| JP2006089795A (en) * | 2004-09-22 | 2006-04-06 | Ntn Corp | Rolling bearing race ring and its producing method, and rolling bearing |
| DE102005051403B3 (en) * | 2005-10-25 | 2007-03-15 | Benteler Automobiltechnik Gmbh | B-column manufacturing method for motor vehicle, involves inserting mold in sectional zone of plate before or during heat formation, and cutting sectional zone after heat formation in mold |
| JP4724538B2 (en) * | 2005-11-22 | 2011-07-13 | 新日本製鐵株式会社 | Forming method by transfer press and transfer press apparatus |
| DE102009050533A1 (en) * | 2009-10-23 | 2011-04-28 | Thyssenkrupp Sofedit S.A.S | Method and hot forming plant for producing a hardened, hot formed workpiece |
| JP5327106B2 (en) * | 2010-03-09 | 2013-10-30 | Jfeスチール株式会社 | Press member and manufacturing method thereof |
-
2011
- 2011-07-06 SE SE1100523A patent/SE1100523A1/en unknown
-
2012
- 2012-07-04 JP JP2014518485A patent/JP2014524979A/en active Pending
- 2012-07-04 KR KR1020147003040A patent/KR20140051934A/en not_active Withdrawn
- 2012-07-04 US US13/261,782 patent/US20150090378A1/en not_active Abandoned
- 2012-07-04 EP EP12808151.0A patent/EP2729587A4/en not_active Withdrawn
- 2012-07-04 CN CN201280027136.0A patent/CN103582707A/en active Pending
- 2012-07-04 WO PCT/SE2012/000104 patent/WO2013006108A1/en not_active Ceased
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO1999002744A1 (en) * | 1997-07-10 | 1999-01-21 | Skf Engineering & Research Centre B.V. | Method for performing a heat treatment on metallic rings, and bearing ring thus obtained |
| WO2004022794A1 (en) * | 2002-09-04 | 2004-03-18 | Colorado School Of Mines | Method for producing steel with retained austenite |
| JP2005177805A (en) * | 2003-12-19 | 2005-07-07 | Nippon Steel Corp | Hot press molding method |
| US20100139821A1 (en) * | 2008-10-16 | 2010-06-10 | Hubertus Giefers | Method for producing a workpiece, a workpiece and use of a workpiece |
| WO2010150683A1 (en) * | 2009-06-22 | 2010-12-29 | 新日本製鐵株式会社 | Hot press-forming method for steel sheets, hot press-forming device for steel sheets, and steel formed member |
Non-Patent Citations (1)
| Title |
|---|
| See also references of EP2729587A4 * |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP3548641B1 (en) | 2016-11-29 | 2020-08-26 | Tata Steel IJmuiden B.V. | Method for manufacturing a hot-formed article, and obtained article |
Also Published As
| Publication number | Publication date |
|---|---|
| CN103582707A (en) | 2014-02-12 |
| SE535821C2 (en) | 2013-01-02 |
| KR20140051934A (en) | 2014-05-02 |
| EP2729587A4 (en) | 2015-03-18 |
| SE1100523A1 (en) | 2013-01-02 |
| JP2014524979A (en) | 2014-09-25 |
| EP2729587A1 (en) | 2014-05-14 |
| US20150090378A1 (en) | 2015-04-02 |
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