US20040065394A1 - Warm hydro-forming method and apparatus for aluminum alloys - Google Patents

Warm hydro-forming method and apparatus for aluminum alloys Download PDF

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Publication number
US20040065394A1
US20040065394A1 US10/428,532 US42853203A US2004065394A1 US 20040065394 A1 US20040065394 A1 US 20040065394A1 US 42853203 A US42853203 A US 42853203A US 2004065394 A1 US2004065394 A1 US 2004065394A1
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US
United States
Prior art keywords
tube component
hydro
forming
die
predetermined temperature
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.)
Abandoned
Application number
US10/428,532
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English (en)
Inventor
Seong Ryu
Sang Lee
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Korea Institute of Machinery and Materials KIMM
Sungwoo Hitech Co Ltd
Original Assignee
Korea Institute of Machinery and Materials KIMM
Sungwoo Hitech Co Ltd
Priority date (The priority date 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 date listed.)
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Application filed by Korea Institute of Machinery and Materials KIMM, Sungwoo Hitech Co Ltd filed Critical Korea Institute of Machinery and Materials KIMM
Assigned to KOREA INSTITUTE OF MACHINERY & MATERIALS, SUNGWOO HITECH CO., LTD. reassignment KOREA INSTITUTE OF MACHINERY & MATERIALS ASSIGNMENT OF ASSIGNORS INTEREST (SEE DOCUMENT FOR DETAILS). Assignors: LEE, SANG YONG, RYU, SEONG JI
Publication of US20040065394A1 publication Critical patent/US20040065394A1/en
Abandoned legal-status Critical Current

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Classifications

    • 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
    • B21D26/00—Shaping without cutting otherwise than using rigid devices or tools or yieldable or resilient pads, i.e. applying fluid pressure or magnetic forces
    • B21D26/02—Shaping without cutting otherwise than using rigid devices or tools or yieldable or resilient pads, i.e. applying fluid pressure or magnetic forces by applying fluid pressure
    • B21D26/033—Deforming tubular bodies
    • B21D26/041—Means for controlling fluid parameters, e.g. pressure or temperature
    • 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
    • B21D26/00—Shaping without cutting otherwise than using rigid devices or tools or yieldable or resilient pads, i.e. applying fluid pressure or magnetic forces
    • B21D26/02—Shaping without cutting otherwise than using rigid devices or tools or yieldable or resilient pads, i.e. applying fluid pressure or magnetic forces by applying fluid pressure
    • B21D26/033—Deforming tubular bodies
    • 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
    • B21D26/00—Shaping without cutting otherwise than using rigid devices or tools or yieldable or resilient pads, i.e. applying fluid pressure or magnetic forces
    • B21D26/02—Shaping without cutting otherwise than using rigid devices or tools or yieldable or resilient pads, i.e. applying fluid pressure or magnetic forces by applying fluid pressure
    • B21D26/033—Deforming tubular bodies
    • B21D26/045—Closing or sealing means

Definitions

  • a hydro-forming method is a tube-forming method using hydraulic pressure, and is generally performed at a normal temperature range of between 10 and 30 degrees Celsius.
  • Tube hydro-forming technology is widely used in the automotive industry. For example, this technology is used for manufacturing various components of a vehicle such as body structure components, and is cost-effective.
  • a conventional aluminum tube hydro-forming method includes a softening process for a high strength aluminum tube 100 in order to secure elongation for forming a component (S 110 ).
  • the tube 100 is then, as shown in FIG. 9, loaded on a lower die 101 of a pressing machine (S 120 ). Subsequently, in a state in which an upper die 103 descends, as shown in FIG. 10, hydraulic cylinders 105 and 107 axially compress the tube 100 , and thereby creating a seal in the bore of the tube 100 (S 130 ).
  • Hydraulic pressure is then supplied into the tube 100 , so that the tube 100 is expanded to forming surfaces 109 and 111 by the hydraulic pressure and axial force transmitted from the hydraulic cylinders 105 and 107 (S 140 ).
  • the tube 100 is taken out from the upper and lower dies 101 and 103 .
  • the fully formed tube component 100 then undergoes a hardening process to increase its strength (S 150 ).
  • a warm hydro-forming method for forming a tube component of aluminum alloys that is disposed in a hydro-forming apparatus along a forming surface of a first die and a second die, by a compressing force of hydraulic cylinders disposed at both ends of the tube component and hydraulic pressure supplied to the tube component, wherein hydro-forming of the tube component is performed while it is in a heated state by supplying forming hydraulic pressure into the tube component, after increasing a temperature of the tube component to a predetermined temperature within a predetermined temperature range in a state such that the tube component is charged by hydraulic pressure just before hydro-forming.
  • the hydraulic pressure is supplied into the tube component by one of water, a water-soluble liquid, and an oily liquid that can be used as pressure-transmitting medium in the predetermined temperature range.
  • the tube component is made of an aluminum-based material.
  • the hydro-forming method for aluminum alloys comprises: loading a tube component made of an aluminum alloy on a die of a hydro-forming apparatus; bringing a first die and a second die together in a state in which the tube component is loaded, and sealing and axially compressing the tube component by an operation of a hydraulic cylinder disposed on each side of the tube component; heating the tube component to a temperature within a predetermined temperature range; forming the tube component along forming surfaces formed on the first die and the second die by providing an axial compressing force of the hydraulic cylinder and supplying hydraulic pressure into the tube component, when the tube component is heated to the predetermined temperature; and taking the formed tube component out of the first and second dies, and cooling the tube component.
  • the hydro-forming apparatus for an aluminum alloy comprises a first die, a second die, a pair of hydraulic cylinders, and a heating unit.
  • the first die and the second die define forming surfaces for a tube component, and the tube component is compressed between the first and second dies.
  • the hydraulic cylinders are configured to axially compress both sides of the tube component and to supply hydraulic pressure for tube forming.
  • the heating unit is disposed in at least one of the first and second dies at positions corresponding to the forming surfaces of the first and second dies, and the heating unit heats the tube component.
  • the heating unit is a heating coil that is operated in response to an electrical signal of a control unit, and the heating coil heats the tube component to a predetermined temperature.
  • FIG. 1 is a flowchart for a warm tube hydro-forming method according to the preferred embodiment of the present invention
  • FIGS. 2 to 6 show successive states of a hydro-forming apparatus according to the preferred embodiment of the present invention
  • FIG. 7 shows relations between tensile strength and elongation according to temperatures of a high strength aluminum alloy (AL 7075);
  • FIG. 8 is a flowchart for the tube hydro-forming method according to the prior art.
  • FIGS. 9 to 12 show successive states of the hydro-forming apparatus according to the prior art.
  • the warm hydro-forming method according to the preferred embodiment of the present invention uses the variation of elongation characteristics of aluminum alloys according to temperature, such that if the temperature of aluminum alloys increases to a high range (approximately between 50 and 300 degrees Celsius), its strength decreases and elongation rapidly increases, and if its temperature decreases back to a normal range (approximately between 10 and 30 degrees Celsius), its strength increases and elongation decreases to the initial values. Therefore, the warm hydro-forming method according to the preferred embodiment of the present invention is performed at a high temperature range (approximately between 50 and 300 degrees Celsius) without performing a softening process through thermal treatment, so that forming characteristics and desired strength can simultaneously be obtained.
  • a warm hydro-forming apparatus includes a lower die 1 disposed in a lower portion of a pressing device (not shown) and an upper die 5 disposed above the lower die 1 .
  • the upper die 5 moves down toward the lower die 1 , and a tube component 3 is compressed between the lower and upper dies 1 and 5 .
  • a left hydraulic cylinder 7 and a right hydraulic cylinder 9 are respectively disposed on both sides of the lower die 1 , and they are configured to be inserted into both ends of the tube component 3 , so that they may axially compress the tube component 3 and create a seal in a bore thereof.
  • the left and right hydraulic cylinders 7 and 9 supply a pressure transmitting medium into the tube component 3 , thereby supplying hydraulic pressure into the tube component 3 .
  • An upper forming surface 11 is provided at a bottom surface of the upper die 5
  • a lower forming surface 13 is provided at an upper surface of the lower die 1 .
  • a heating unit is disposed in the lower and upper dies 1 and 5 behind the forming surfaces 11 and 13 , that is, at positions corresponding to the forming surfaces 11 and 13 .
  • the heating unit may be a heating coil 21 that operates in response to an electrical signal of a control unit 20 .
  • the heating coil 21 is designed to emit heat to a predetermined temperature. In this manner, heat emitted form the heating coil 21 heats the tube component 3 and the pressure transmitting medium to the predetermined temperature.
  • the heating coil 21 is provided in order to heat the tube component 3 to a desired temperature.
  • the tube component 3 can be heated by supplying a hot pressure transmitting medium that is heated by a separate heating apparatus, into the tube component 3 , without the heating coil 21 disposed inside the upper and lower dies 1 and 5 .
  • the warm hydro-forming method according to the preferred embodiment of the present invention can, as shown FIGS. 2 to 6 , be applied to the above stated hydro-forming apparatus, as follows.
  • a temperature of the tube component 3 is raised to a predetermined temperature within a predetermined temperature range by the heating coil 21 just before the expansion of the tube component 3 , in a state such that the hydraulic pressure is provided into the tube component 3 , and the hydraulic pressure is then finally provided into the tube component 3 so that the tube component 3 is formed in a heated state.
  • the warm hydro-forming method according to the preferred embodiment of the present invention uses a temperature-dependant elongation characteristic of the high strength aluminum alloy.
  • the strength of the tube component 3 drops slightly, but elongation thereof drastically increases, so that a sufficient shape change can be secured in that temperature range.
  • the predetermined temperature range in which elongation of the tube component 3 drastically increases may preferably be in a range of between 50 and 300 degrees Celsius.
  • FIG. 7 shows relations between tensile strength and elongation of the tube component 3 (made of aluminum alloy material (AL 7075 )) according to temperature.
  • the tensile strength is between 570 MPa and 525 MPa (Mega Pascal), and elongation is between 11% and 14%.
  • the tensile strength drastically decreases to a range of between 285 MPa and 40 MPa, but elongation drastically increases to a range of between 23% and 70%.
  • a hydraulic fluid that has stability at the high temperature range (for example, 50 to 300 degrees Celsius) must be used as the hydraulic pressure-transmitting medium.
  • Water, a water-soluble liquid, or an oily liquid that can be used as a pressure-transmitting medium in the predetermined temperature range (between 50 and 300 degrees Celsius) can be used as a pressure-transmitting medium of the hydraulic cylinders 7 and 9 . More specifically, in the present embodiment of the present invention, silicon oil can be used as the hydraulic fluid.
  • the aluminum alloy tube component 3 is first loaded between the lower and upper dies 1 and 5 (S 10 ).
  • the formed tube component 3 is taken from the lower and upper dies 1 and 5 , and it is then cooled.
  • the tube component 3 recovers its strength at the initial normal temperature, and elongation of the tube component 3 substantially decreases. Therefore, the tube component 3 recovers its mechanical characteristics of the normal temperature (S 50 ).
  • the warm hydro-forming method and apparatus use elongation characteristics of the high strength aluminum alloy according to its temperature, and tube hydro-forming is performed in a state in which forming characteristics are secured in a predetermined temperature range. Therefore, in the warm hydro-forming method according to the present invention, softening and hardening processes of the conventional hydro-forming method can be eliminated, so forming quality and productivity can be improved.
US10/428,532 2002-10-04 2003-05-02 Warm hydro-forming method and apparatus for aluminum alloys Abandoned US20040065394A1 (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
KR10-2002-0060550 2002-10-04
KR1020020060550A KR20040031175A (ko) 2002-10-04 2002-10-04 알루미늄 합금의 온간 액압 성형 방법 및 그 장치

Publications (1)

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US (1) US20040065394A1 (ko)
KR (1) KR20040031175A (ko)
DE (1) DE10317873A1 (ko)

Cited By (17)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20050186302A1 (en) * 2004-02-24 2005-08-25 Sungwoo Hitech Co., Ltd. Warm hydro-forming device
US20070073354A1 (en) * 2005-09-26 2007-03-29 Knudson Mark B Neural blocking therapy
US20080256778A1 (en) * 2007-04-20 2008-10-23 Gm Global Technology Operations, Inc. Method for Joining Tubes
JP2010221232A (ja) * 2009-03-19 2010-10-07 Tokyo Metropolitan Univ ハイドロフォーム成形方法及びハイドロフォーム成形装置
ITMI20101820A1 (it) * 2010-10-05 2012-04-06 Beretta Armi Spa Procedimento per la realizzazione di caricatori di armi da fuoco, in particolare pistole e/o simili, e caricatore ottenuto mediante tale procedimento
CN102829999A (zh) * 2012-08-03 2012-12-19 江苏大学 实验用温热型高速成形装置
CN103846331A (zh) * 2014-03-27 2014-06-11 北京航空航天大学 大型薄壁复杂特征板材双向加压充液成形方法
CN104525752A (zh) * 2014-12-08 2015-04-22 无锡朗贤汽车组件研发中心有限公司 等截面硼钢钢管的热成形及水冷工艺
CN104985043A (zh) * 2015-01-30 2015-10-21 西北工业大学 金属导体管件的电磁感应加热胀形装置及成形方法
CN105537363A (zh) * 2015-12-15 2016-05-04 南京航空航天大学 一种铝合金空心件温胀形成形装置及方法
US20170095853A1 (en) * 2014-06-18 2017-04-06 Sumitomo Heavy Industries, Ltd. Forming system and forming method
CN107052080A (zh) * 2017-03-09 2017-08-18 江苏兴洋管业股份有限公司 一种热压三通管坯分区加热控温设备及其加热控温方法
US20180054924A1 (en) * 2016-08-19 2018-02-22 Dell Products, Lp Liquid Cooling System with Extended Microchannel and Method Therefor
CN109604412A (zh) * 2018-11-08 2019-04-12 北京航星机器制造有限公司 一种铝合金弹体用内埋式进气道超塑成形方法
CN110480258A (zh) * 2019-07-18 2019-11-22 安徽润盈建材有限公司 一种金属竹子连续模具成型扩张成型工艺
CN111261398A (zh) * 2020-03-16 2020-06-09 宁波锐科磁业有限公司 一种制备钕铁硼磁环的热压装置、热压系统及制备方法
US10960452B2 (en) * 2018-11-19 2021-03-30 Dalian University Of Technology Method for pressure forming of aluminum alloy special-shaped tubular component by using ultra low temperature medium

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KR100508981B1 (ko) * 2002-12-09 2005-08-17 주식회사 성우하이텍 알루미늄 합금의 온간 액압 성형 장치 및 그 제어방법
KR100775809B1 (ko) * 2006-11-09 2007-11-12 주식회사 성우하이텍 알루미늄 합금의 온간 하이드로 포밍 장치 및 그 제어방법
KR100775808B1 (ko) * 2006-11-09 2007-11-12 주식회사 성우하이텍 온간 액압성형시스템용 유체가열장치
KR100775807B1 (ko) * 2006-11-09 2007-11-12 주식회사 성우하이텍 온간 액압성형시스템용 금형유닛
KR100881833B1 (ko) * 2007-04-05 2009-02-03 현대하이스코 주식회사 관 소재를 이용한 초고강도 자동차용 부품의 제조 방법
DE102007018281A1 (de) 2007-04-18 2008-10-23 Volkswagen Ag Werkzeug zum Innenhochdruckformen, sowie Verfahren zum Innenhochdruckformen
KR200485232Y1 (ko) * 2017-03-06 2017-12-11 삼원동관 주식회사 분지형 파이프 성형 장치 및 이에 의하여 성형된 분지형 파이프
CN109821962B (zh) * 2019-03-26 2023-11-14 桂林电子科技大学 金属双层管冲击液压复合成形装置及方法

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US6349583B1 (en) * 1999-06-24 2002-02-26 Benteler Ag Method and device for forming a hollow metallic workpiece by inner pressure

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JP3022506B1 (ja) * 1998-09-09 2000-03-21 株式会社オプトン バルジ加工装置
EP1220725A1 (en) * 1999-10-15 2002-07-10 Cosma International Inc. Method for hydroforming an aluminum tubular blank

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US6067831A (en) * 1997-12-23 2000-05-30 Gkn Sankey Hydroforming process
US6349583B1 (en) * 1999-06-24 2002-02-26 Benteler Ag Method and device for forming a hollow metallic workpiece by inner pressure

Cited By (23)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20050186302A1 (en) * 2004-02-24 2005-08-25 Sungwoo Hitech Co., Ltd. Warm hydro-forming device
US7231793B2 (en) * 2004-02-24 2007-06-19 Sungwoo Hitech Co., Ltd. Warm hydro-forming device
US20070073354A1 (en) * 2005-09-26 2007-03-29 Knudson Mark B Neural blocking therapy
US20080256778A1 (en) * 2007-04-20 2008-10-23 Gm Global Technology Operations, Inc. Method for Joining Tubes
US8020272B2 (en) * 2007-04-20 2011-09-20 GM Global Technology Operations LLC Method for joining tubes
JP2010221232A (ja) * 2009-03-19 2010-10-07 Tokyo Metropolitan Univ ハイドロフォーム成形方法及びハイドロフォーム成形装置
ITMI20101820A1 (it) * 2010-10-05 2012-04-06 Beretta Armi Spa Procedimento per la realizzazione di caricatori di armi da fuoco, in particolare pistole e/o simili, e caricatore ottenuto mediante tale procedimento
WO2012046160A1 (en) * 2010-10-05 2012-04-12 Fabbrica D'armi Pietro Beretta S.P.A. Process for making loaders of firearms, in particular guns and the like, and a loader obtained through such a process
CN102829999A (zh) * 2012-08-03 2012-12-19 江苏大学 实验用温热型高速成形装置
CN103846331A (zh) * 2014-03-27 2014-06-11 北京航空航天大学 大型薄壁复杂特征板材双向加压充液成形方法
CN103846331B (zh) * 2014-03-27 2016-05-25 北京航空航天大学 大型薄壁复杂特征板材双向加压充液成形方法
US10040110B2 (en) * 2014-06-18 2018-08-07 Sumitomo Heavy Industries, Ltd. Forming system and forming method
US20170095853A1 (en) * 2014-06-18 2017-04-06 Sumitomo Heavy Industries, Ltd. Forming system and forming method
CN104525752A (zh) * 2014-12-08 2015-04-22 无锡朗贤汽车组件研发中心有限公司 等截面硼钢钢管的热成形及水冷工艺
CN104985043A (zh) * 2015-01-30 2015-10-21 西北工业大学 金属导体管件的电磁感应加热胀形装置及成形方法
CN105537363A (zh) * 2015-12-15 2016-05-04 南京航空航天大学 一种铝合金空心件温胀形成形装置及方法
US20180054924A1 (en) * 2016-08-19 2018-02-22 Dell Products, Lp Liquid Cooling System with Extended Microchannel and Method Therefor
US10264713B2 (en) * 2016-08-19 2019-04-16 Dell Products, Lp Liquid cooling system with extended microchannel and method therefor
CN107052080A (zh) * 2017-03-09 2017-08-18 江苏兴洋管业股份有限公司 一种热压三通管坯分区加热控温设备及其加热控温方法
CN109604412A (zh) * 2018-11-08 2019-04-12 北京航星机器制造有限公司 一种铝合金弹体用内埋式进气道超塑成形方法
US10960452B2 (en) * 2018-11-19 2021-03-30 Dalian University Of Technology Method for pressure forming of aluminum alloy special-shaped tubular component by using ultra low temperature medium
CN110480258A (zh) * 2019-07-18 2019-11-22 安徽润盈建材有限公司 一种金属竹子连续模具成型扩张成型工艺
CN111261398A (zh) * 2020-03-16 2020-06-09 宁波锐科磁业有限公司 一种制备钕铁硼磁环的热压装置、热压系统及制备方法

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Publication number Publication date
DE10317873A1 (de) 2004-04-22
KR20040031175A (ko) 2004-04-13

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