JP3761820B2 - Metal member forming method - Google Patents

Metal member forming method Download PDF

Info

Publication number
JP3761820B2
JP3761820B2 JP2002043277A JP2002043277A JP3761820B2 JP 3761820 B2 JP3761820 B2 JP 3761820B2 JP 2002043277 A JP2002043277 A JP 2002043277A JP 2002043277 A JP2002043277 A JP 2002043277A JP 3761820 B2 JP3761820 B2 JP 3761820B2
Authority
JP
Japan
Prior art keywords
metal member
mold
gas
heating
forming
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.)
Expired - Fee Related
Application number
JP2002043277A
Other languages
Japanese (ja)
Other versions
JP2003154415A (en
Inventor
治男 渡辺
博進 井関
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.)
Aisin Takaoka Co Ltd
Original Assignee
Aisin Takaoka 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.)
Filing date
Publication date
Application filed by Aisin Takaoka Co Ltd filed Critical Aisin Takaoka Co Ltd
Priority to JP2002043277A priority Critical patent/JP3761820B2/en
Priority to US10/234,227 priority patent/US20040040636A1/en
Priority to GB0220482A priority patent/GB2379180B/en
Priority to DE10240876A priority patent/DE10240876B4/en
Publication of JP2003154415A publication Critical patent/JP2003154415A/en
Application granted granted Critical
Publication of JP3761820B2 publication Critical patent/JP3761820B2/en
Anticipated expiration legal-status Critical
Expired - Fee Related legal-status Critical Current

Links

Images

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
    • B21D37/00—Tools as parts of machines covered by this subclass
    • B21D37/16—Heating or cooling
    • 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
    • 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
    • C21D9/00—Heat treatment, e.g. annealing, hardening, quenching or tempering, adapted for particular articles; Furnaces therefor
    • C21D9/08—Heat treatment, e.g. annealing, hardening, quenching or tempering, adapted for particular articles; Furnaces therefor for tubular bodies or pipes
    • C21D9/085—Cooling or 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
    • C21D7/00—Modifying the physical properties of iron or steel by deformation
    • C21D7/02—Modifying the physical properties of iron or steel by deformation by cold working
    • C21D7/10—Modifying the physical properties of iron or steel by deformation by cold working of the whole cross-section, e.g. of concrete reinforcing bars
    • C21D7/12—Modifying the physical properties of iron or steel by deformation by cold working of the whole cross-section, e.g. of concrete reinforcing bars by expanding tubular bodies

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)
  • Fluid Mechanics (AREA)
  • Shaping Metal By Deep-Drawing, Or The Like (AREA)

Description

【０００１】
【発明の属する技術分野】
本発明は金属部材の成形性の向上及び高強度化を図り得る金属部材成形方法に関する。
【０００２】
【従来の技術】
金属部材成形方法としてハイドロフォーム法が知られている。ハイドロフォーム法は、中空室を有する筒形状をなす金属部材と、目標形状に設定された成形型面を有する成形型とを用い、金属部材の中空室に水を供給することにより、金属部材の壁を膨出変形させ、膨出変形させた金属部材の壁を成形型の成形型面に密接させて成形する技術である。
【０００３】
【発明が解決しようとする課題】
上記したハイドロフォーム法によれば、金属部材の中空室に水を供給することにより、金属部材の壁を膨出変形させて成形を行うことができるものの、金属部材の成形性と高強度化の双方を満足させるには限界があった。
【０００４】
殊に、最近の自動車部品等では、軽量化のため材料を薄肉化することが要請されているが、薄肉化した場合には、金属部材を成形する際の成形力を小さくできるものの、金属部材の高強度化には限界がある。
【０００５】
また材料が鉄系の場合には、軽量化のため材料を薄肉化しつつ、合金元素の増量によりハイテン化（高張力鋼化）させることも要請されているが、このように材料がハイテン化されている場合には、金属部材の高強度化を図り得るものの、材料の伸びが低下するため、材料の成形性が低下し、ハイドロフォーム法で金属部材を膨出変形させる際に亀裂等が発生するおそれがある。
【０００６】
本発明は上記した実情に鑑みてなされたものであり、金属部材の成形性及び高強度化の双方を達成することができる金属部材成形方法を提供することを課題とする。
【０００７】
【課題を解決するための手段】
本発明に係る金属部材成形方法は、中空室を有する筒形状をなす金属部材と、成形型面と該成形型面を冷却する冷却手段を有する成形型とを用い、急冷強化可能な温度領域に加熱した前記金属部材の中空室の気体の内圧を高めることにより、前記金属部材の壁を膨出変形させ、膨出変形させた前記金属部材の壁を成形型の成形型面に密接させて成形すると同時に前記冷却手段によって冷却された前記成形型面によって急冷強化させる成形急冷強化工程を実施することを特徴とするものである。
【０００８】
本発明に係る金属部材成形方法によれば、まず、急冷強化可能な温度領域に金属部材を加熱する。そして成形急冷強化工程では、金属部材の中空室の気体の内圧を高めることにより、金属部材の壁を膨出変形させる。このとき金属部材の中空室には気体が収容されているため、ハイドロフォーム法のように金属部材の中空室に水が収容されている場合に比較して、金属部材の温度を高めに維持することができる。
【０００９】
また本発明に係る金属部材成形方法によれば、上記したように膨出変形させた金属部材の壁を成形型の成形型面に密接させて成形すると共に急冷強化させる。このように金属部材を膨出変形させる際に、金属部材は急冷強化可能な温度領域に加熱されているため、金属部材の伸びを確保することができる。故に、金属部材の塑性変形性を向上させ、金属部材の膨出変形性、成形性を高めることができる。
【００１０】
更に上記した成形急冷強化工程では、膨出変形させた金属部材の壁を成形型の成形型面に密接させることにより、金属部材を急冷強化させ、金属部材の高強度化を図ることができる。
【００１３】
前記金属部材を既述した金属部材成形方法によって成形することで、その金属部材の成形性及び高強度化の双方が達成されることとなる。
【００１４】
また、本発明は、中空室を有する筒形状をなす金属部材が装填される成形型と、前記成形型内で加熱された前記金属部材の前記中空室に気体を供給する気体供給手段と、前記成形型を冷却することにより、該成形型に装填された前記金属部材を冷却する冷却手段と、を含む、金属部材成形装置を用いて実施される。前記金属部材成形装置によれば、金属部材の変形及び冷却が、成形型内で連続的に行われる。すなわち、金属部材の成形及び熱処理が連続的に行われる。
【００１５】
前記金属部材成形装置は、さらに、前記成形型内に装填された前記金属部材を加熱する手段を、有することを特徴とする。前記金属部材成形装置によれば、金属部材の加熱、変形及び冷却が、成形型内で連続的に行われる。すなわち、金属部材の成形及び熱処理が連続的に行われ、作業性の向上が図られる。
【００１６】
【発明の実施の形態】
本発明に係る金属部材成形方法、金属部材及び金属部材成形装置によれば、次の実施形態の少なくとも一つを採用することができる。
【００１７】
・出発材としての金属部材は中空室を有する筒形状をなす。筒形状としては円筒形状、角筒形状を採用することができる。成形急冷強化工程を実施する前の金属部材としては、直状の筒形状でも良いし、曲成部、凹部、凸部の少なくとも一つを有する筒形状でも良い。金属部材は、一体成形品でも良いし、複数の素材を接合したものでも良い。
【００１８】
金属部材の材質としては鉄系（ハイテン鋼、ステンレス鋼等の合金鋼を含む）、チタン系、アルミニウム系または銅系である実施形態を採用することができる。但しこれらに限定されるものではない。ハイテン鋼は引張強さが大きい鋼で形成された高張力鋼を意味する。ハイテン鋼としては、成形急冷強化工程を施す前の段階で、引張強さ５００ＭＰａ（≒５０ｋｇｆ／ｍｍ2）以上の鉄系金属、引張強さ６００ＭＰａ以上の鉄系金属、引張強さ８００ＭＰａ以上の鉄系金属、引張強さ１０００ＭＰａ以上の鉄系金属、引張強さ１５００ＭＰａ以上の鉄系金属を採用することができる。一般的には、ハイテン鋼は強度が高いものの、塑性変形性が必ずしも充分ではない。本発明方法及び本発明装置によれば、これらの金属部材は急冷強化に先だって加熱されるため、金属部材の塑性変形性が向上する。このため金属部材の材質がハイテン化されている場合のように塑性変形性が必ずしも充分ではない場合であっても、金属部材の膨出変形性、成形性を高めることができる。よって、金属部材の成形形状が異形である場合であっても、金属部材の成形度合が大きい場合であっても、金属部材の成形性を良好に確保することができる。
【００１９】
・金属部材の加熱は、加熱炉の炉室に金属部材を保持する操作、金属部材を誘導加熱する誘導加熱操作、金属部材に通電する抵抗加熱操作の少なくとも１種で実行される実施形態を採用することができる。これらの各操作の少なくとも２種を併用することもできる。即ち、加熱炉の炉室に金属部材を保持する操作を行った後に、金属部材を誘導加熱する誘導加熱操作を行うことができる。また、加熱炉の炉室に金属部材を保持する操作を行った後に、金属部材に通電する抵抗加熱操作を行うことができる。更に加熱炉の炉室に金属部材を保持する操作を行うことなく、金属部材を誘導加熱する誘導加熱操作と、金属部材に通電する抵抗加熱操作とを行うことができる。金属部材を誘導加熱する誘導加熱操作と、金属部材に通電する抵抗加熱操作とは、時間的に同時にまたは時間的にずらして行うこともできる。
【００２０】
・加熱炉の炉室に金属部材を保持する操作は、加熱炉の炉室を非酸化性雰囲気とした状態で実行される実施形態を採用することができる。非酸化性雰囲気としては、真空雰囲気、還元性ガス雰囲気、不活性ガス雰囲気の少なくとも１種を採用することができる。還元性ガス雰囲気としては、ＣＯガス雰囲気、ＣＯを含むガス雰囲気の少なくとも１種を採用することができる。不活性ガス雰囲気としては窒素ガス雰囲気、アルゴンガス等の希ガス雰囲気を採用することができる。
【００２１】
・金属部材を誘導加熱する誘導加熱操作は、成形型の成形型面に対面する金属部材に誘導加熱用の導電部材を接近させた状態で、導電部材に交番電流を通電して金属部材を誘導加熱することにより実行される実施形態を採用することができる。誘導加熱用の導電部材は、コイル形状であっても良いし、板状であっても良く、要するに金属部材を誘導加熱できれば良い。誘導加熱用の導電部材に通電する交番電流の周波数としては、金属部材を誘導加熱できる周波数の範囲内において、金属部材の材質、設備コスト、誘導加熱性等を考慮して適宜選択することができ、低周波の周波数領域、中周波の周波数領域、高周波の周波数領域を必要に応じて採用することができる。周波数としては、例えば０．５ｋＨｚ〜５０００ｋＨｚ、殊に１ｋＨｚ〜２０００ｋＨｚを採用することができる。但しこれらの周波数に限定されるものではない。
【００２２】
なお、導電部材に高周波の交番電流を通電して金属部材を誘導加熱する場合には、金属部材のうち導電部材に近接している表層を効率よく加熱できる近接効果と、金属部材の表層を電流が流れる表皮効果とを期待できるため、金属部材の表層を効率的に加熱することができる。
【００２３】
・金属部材に通電する抵抗加熱操作は、成形型の成形型面に対面する金属部材に通電端子を接続した状態で、通電端子から金属部材に通電して金属部材をジュール熱で加熱することにより実行される実施形態を採用することができる。通電端子から金属部材に通電する電流としては直流でも良いし、交番電流（交流）でも良い。交番電流の場合には、周波数としては、金属部材の材質、設備コスト、抵抗加熱性等を考慮して、低周波の周波数領域、中周波の周波数領域、高周波の周波数領域を必要に応じて採用することができる。周波数としては、例えば０．５ｋＨｚ〜５０００ｋＨｚ、殊に１ｋＨｚ〜２０００ｋＨｚを採用することができる。但しこれらの周波数に限定されるものではない。なお、通電端子から金属部材に高周波の交番電流を通電する場合には、金属部材の表層を電流が流れる表皮効果を期待できるため、金属部材の表層を効率的に加熱することができる。
【００２４】
・金属部材は鉄系であり、金属部材をＡ１変態点（焼入可能温度）以上の温度領域に加熱する実施形態を採用することができる。Ａ１変態点以上は、オーステナイト生成温度よりも高い温度領域を意味する。場合によっては、Ａ３変態点以上の温度領域に加熱する実施形態を採用することもできる。なお金属部材の加熱温度の上限としては、金属部材の母材の液相生成温度とすることが好ましい。
【００２５】
・成形急冷強化工程では、金属部材の壁を成形型の成形型面に密接させることにより、金属部材の少なくとも一部を焼入してマルテンサイト化を促進させることができる。このように焼入すれば、金属部材の強化を図り得る。また、急冷強化にあたり、マルテンサイトと共にまたはマルテンサイトに代えて、トルースタイトまたはソルバイト等が生成する形態でも良い。トルースタイトまたはソルバイトは、マルテンサイトが生成するときの冷却速度よりも冷却速度が遅い場合に生成し易い。
【００２６】
・金属部材が鉄系である場合には、焼入性を高めるべく、焼入倍数が高い合金元素を含むことができる。焼入倍数が高い合金元素としては、炭素、マンガン、シリコン、ニッケル、クロム、モリブデンが挙げられ、これらの合金元素の少なくとも１種を含むことができる。金属部材が鉄系である場合には、材料をハイテン化させるには、上記した合金元素の少なくとも１種（例えば炭素）の含有量が増加されることが多い。
【００２７】
・成形型は、成形型を冷却させる冷却手段を備えている実施形態を採用することができる。冷却手段としては、成形型の内部に冷却通路を形成し、冷却通路に冷却水や冷媒ガス等の冷却媒体を供給する方式、成形型の成形型面に冷却水や冷媒ガス等の冷却媒体を接触させる方式の少なくとも１種を採用することができる。成形型の材質としては、炭素鋼や合金鋼等の熱伝導性が良好で且つ耐久性の良い金属を例示することができる。
【００２８】
・本発明方法及び本発明装置によれば、金属部材の中空室の気体の内圧を高めることにより、金属部材の壁を膨出変形させ、成形型の成形型面に密接させる。金属部材の中空室の気体の内圧を高める操作は、金属部材の中空室に気体を供給することにより実行される実施形態を採用することができる。金属部材の中空室に供給する気体としては、空気、窒素ガス、窒素富化ガス、アルゴンガス、アルゴン富化ガスの少なくとも１種を採用することができる。窒素富化ガスは窒素濃度が高いガスをいう。アルゴン富化ガスはアルゴンガスの濃度が高いガスをいう。
【００２９】
・金属部材の中空室に気体を供給する操作としては、高圧気体を供給できる高圧気体供給源から実行される実施形態を採用することができる。高圧気体の圧力は、金属部材の成形性を考慮すると高いほうが好ましい。高圧気体の圧力としては、例えば１０ＭＰａ以上、１５ＭＰａ以上、２０ＭＰａ以上、３０ＭＰａ以上を設定できるが、実用性を考慮すると、１５〜２５ＭＰａ、１７〜２３ＭＰａ、１９〜２１ＭＰａ、２０ＭＰａが好ましい。高圧気体供給源としてはボンベ、工場エア源等を例示することができる。
【００３０】
・金属部材は、中空室に連通すると共に拡開壁面で形成された開口を有している実施形態を採用することができる。この場合、金属部材の拡開壁面の傾斜に対応する傾斜を有するシール具を、金属部材の拡開壁面に直接的にまたは間接的にあてがって金属部材の開口をシールする実施形態を採用することができる。この場合、金属部材の開口を形成する拡開壁面にシール具をあてがうため、金属部材の開口を形成する拡開壁面におけるシールが良好に行われる。従って金属部材の中空室を高圧化させるのに有利となる。
【００３１】
金属部材成形方法としては、金属部材を成形型内に装填（配置）する工程と、成形型内に装填され金属部材を加熱する工程と、成形型内で加熱された金属部材の中空室に気体を供給することにより、該金属部材を塑性変形させ、該金属部材の所定面を成形型の所定面に密接させると同時に、該金属部材が成形型内に挿入された状態で成形型を冷却することにより冷却されている成形型面によって、金属部材を冷却する工程とを含む実施形態を採用することができる。
【００３２】
また、金属部材成形方法としては、金属部材を加熱する工程と、加熱された金属部材を成形型内に装填（配置）する工程と、加熱後に成形型内に装填された金属部材の中空室に気体を供給することにより、該金属部材を塑性変形させ、該金属部材の所定面を成形型の所定面に密接させると同時に、該金属部材が成形型内に挿入された状態で成形型を冷却することにより冷却されている成形型面によって、金属部材を冷却する工程とを含む実施形態を採用することができる。
【００３３】
所望とする形状の付与された金属部材は、既述した金属部材成形方法のいずれか１つの方法によって成形されたものである。金属部材を所望とする形状に成形する際に、既述した金属部材成形方法のいずれか１つの方法を用いることで、その金属部材の成形性及び高強度化の双方を達成することが可能となる。
【００３４】
金属部材成形装置としては、中空室を有する筒形状をなす金属部材が装填される成形型と、成形型内で加熱された金属部材の中空室に気体を供給する気体供給手段と、成形型を冷却することにより、該成形型に装填された金属部材を冷却する冷却手段とを含む実施形態を採用することができる。気体供給手段としては、既述した高圧気体供給源を例示することができ、高圧気体供給源は、ボンベ、バルブ、供給管等を有する。
【００３５】
更に、成形型と気体供給手段と冷却手段とを含む金属部材成形装置においては、成形型内に装填された金属部材を加熱する手段を有するようにしてもよい。この場合、金属部材を加熱する手段としては、例えば、既述した誘導加熱操作や抵抗加熱操作が挙げられる。
【００３６】
【実施例】
（第１実施例）
以下、本発明の第１実施例について図１〜図３を参照して具体的に説明する。本実施例は、出発材としての金属部材１に対して、代表的な急冷強化である焼入強化を行う例である。本実施例に係る成形方法で用いる金属部材１は、中空室１０を有する円筒形状をなしており、鉄系金属で形成されている。焼入前の鉄系金属はハイテン化（高張力鋼化）されており、具体的には、引張強さ６００ＭＰａ（≒６０ｋｇｆ／ｍｍ2）以上の鉄系金属で形成されており、塑性変形性は必ずしも充分ではない。
【００３７】
本実施例によれば、図１に示すように、素管状の金属部材１の両端部に拡開加工を施すことにより、端１２ｃに向かうにつれて拡開する拡開部１２が予め形成されている。拡開部１２の内壁面である拡開壁面１３は、中空室１０に連通する開口１３ｘを形成している。
【００３８】
まず加熱工程では、金属部材１を加熱炉２の炉室２０に所定時間保持し、金属部材１を急冷強化可能な温度領域、つまりＡ１変態点以上の温度領域に加熱する。この場合、必要に応じて、金属部材１をＡ３変態点以上の温度領域に加熱することもできる。これにより金属部材１の組織の全部または一部はオーステナイト化される。加熱炉２の炉室２０は非酸化性雰囲気に保持されているため、加熱中の金属部材１の酸化及び脱炭が抑えられる。非酸化性雰囲気としては、真空雰囲気、還元性ガス雰囲気、アルゴンガス等の不活性ガス雰囲気等を必要に応じて採用することができる。
【００３９】
次に、上記したように目標温度領域に加熱した金属部材１を加熱炉２から取り出し、図２に示すように、その金属部材１を成形型３内に配置（装填）する。成形型３は代表的な金属材料である鋼系材料で形成されており、目標形状に設定された成形型面３１を有する。この場合、金属部材１の壁１ａの強化要請部位が成形型３の成形型面３１に接触しないように、金属部材１を配置することが好ましい。成形型３の内部には、冷却水や冷媒ガス等の冷却媒体が流れる冷却通路３３が冷却手段として形成されている。冷却水や冷媒ガス等の冷却媒体が冷却通路３３に流れると、成形型３は冷却され、被成形物である金属部材１を成形型３の成形型面３１で急冷させることができる。なお、上記した加熱工程の前にまたは加熱工程の途中において、冷却水や冷媒ガス等の冷却媒体を成形型３の冷却通路３３に流して成形型３を冷却しておくことが好ましい。
【００４０】
本実施例に係る成形急冷強化工程では、図２に示すように、金属部材１の拡開部１２の拡開壁面１３の傾斜に対応する傾斜を備えたシール面４４を有する２個１組のシール具４０，４１を用いる。シール具４０，４１は金属または耐火物で形成することができる。一方のシール具４０は気体供給手段としての高圧気体供給源５に接続される通路４０ａを有する。他方のシール具４１は密閉機能を有しているものの、高圧気体供給源５には接続されていない。高圧気体供給源５は高圧の気体を供給するものであり、高圧気体が封入されたボンベ５０と、ボンベ５０を開閉する開閉弁５１を有するバルブ５２と、ボンベ５０に封入されている気体の圧力を検出する圧力検出手段として機能する圧力計５３と、バルブ５２から導出された供給通路として機能する可撓性を有する供給管５４とを有する。
【００４１】
そして図２に示すように、シール具４０，４１を金属部材１の両端の開口１３ｘに嵌め、シール面４４を金属部材１の拡開部１２の拡開壁面１３に直接的にあるいは図略の中間部材を介して間接的にあてがってシールする。この場合、金属部材１の壁１ａと成形型面３１との間には空間Ｗが介在している。
【００４２】
本実施例に係る成形急冷強化工程では、上記したようにシール具４０，４１を金属部材１の拡開部１２の拡開壁面１３にシールした状態で、高圧気体供給源５の高圧（例えば２０ＭＰａ）の気体を金属部材１の中空室１０に供給する。具体的には、高圧気体供給源５の開閉弁５１を開放させることにより、高圧気体供給源５のボンベ５０の高圧の気体を供給管５４及び一方のシール具４０の通路４０ａを経て金属部材１の中空室１０に供給する。
【００４３】
これにより金属部材１の中空室１０の気体の内圧を高め、金属部材１の壁１ａをこれの径方向の外方に膨出変形（塑性変形）させ、成形型３の成形型面３１に密接させる。図３に示すように、これにより金属部材１の壁１ａが成形型面３１に沿って成形される。更に成形と同時に、金属部材１の壁１ａが成形型３の成形型面３１によって急冷されるため、金属部材１の壁１ａは焼入される。
【００４４】
本実施例に係る成形急冷強化工程の直前または途中の段階において、焼入性を高めるべく、冷却水や冷媒ガス等の冷却媒体を成形型３の冷却通路３３に流して成形型３を冷却することが好ましい。
【００４５】
金属部材１の中空室１０に供給する気体としては、空気、窒素ガス、窒素富化ガス、アルゴンガス、アルゴン富化ガスの少なくとも１種を必要に応じて採用することができる。コスト低減を考慮すると、空気を採用することができる。金属部材１の酸化抑制を考慮すると、酸化能力が低いか有しない窒素ガス、窒素富化ガス、アルゴンガス、アルゴン富化ガスを採用することができる。なお、上記したように金属部材１の成形及び焼入が終了すれば、金属部材１とシール具４０，４１とを分離させると共に、所望とする形状の付与された金属部材１を成形型３から分離させる。
【００４６】
以上説明したように本実施例によれば、膨出変形の際に金属部材１は高温領域に加熱されているため、金属部材１を構成する材料がハイテン化された金属材料で形成されて塑性変形性が低下しているといえども、金属部材１の塑性変形性を向上させることができる。このため金属部材１の膨出変形性、ひいては成形性を高めることができる。
【００４７】
更に本実施例によれば、成形急冷強化工程では、膨出変形させた金属部材１の壁１ａを成形型３の成形型面３１に密接させることにより、金属部材１の壁１ａから奪熱し、金属部材１の壁１ａを焼入することができる。これにより金属部材１の壁１ａを強化することができる。即ち、上記したように本実施例によれば、金属部材１の壁１ａの成形性及び高強度化の双方を同時に達成することができる。
【００４８】
このように金属部材１を強化できる本実施例によれば、焼入前の状態で引張強さ６００ＭＰａ（≒６０ｋｇｆ／ｍｍ2）以上の鉄系金属で形成された金属部材１を用いているにもかかわらず、上記した焼入によって、金属部材１を構成している鉄系金属を引張強さ１０００ＭＰａ（≒１００ｋｇｆ／ｍｍ2）以上または１２００ＭＰａ以上、場合によっては１５００ＭＰａ以上に強化させることができる。
【００４９】
本実施例によれば、前述したように、成形急冷強化工程では、膨出変形させた金属部材１の壁１ａを成形型３の成形型面３１に密接させることにより、金属部材１の壁１ａを焼入強化することにしている。従って、加熱工程における金属部材１の加熱温度、成形型３の成形型面３１の冷却能を適宜調整すれば、金属部材１の壁１ａの厚み方向において、成形型３の成形型面３１に対面して密接する一方の表層１ｃ（外側表層）の冷却速度を、成形型３の成形型面３１に背向する他方の表層１ｄ（内側表層）の冷却速度よりも速くできる。
【００５０】
換言すれば、金属部材１の壁１ａの厚み方向において、成形型３の成形型面３１に対面して密接する一方の表層１ｃ（外側表層）の冷却速度よりも、成形型３の成形型面３１に背向する他方の表層１ｄ（内側表層）の冷却速度を遅くできる。従って、金属部材１の壁１ａの厚み方向において、成形型３の成形型面３１に対面して密接する一方の表層１ｃ（外側表層）の焼入性を高めてこの部分の高強度化を図ると共に、成形型３の成形型面３１に背向する他方の表層１ｄ（内側表層）の焼入性を抑えてこの部分の靱性を確保することもできる。即ち、金属部材１の壁１ａの厚み方向において焼入強化の度合を変化させることができ、金属部材１の高強度化と耐衝撃性の双方を高める効果も期待することができる。
【００５１】
加えて本実施例によれば、金属部材１の拡開部１２の拡開壁面１３の傾斜に対応する傾斜を備えたシール面４４を有するシール具４０，４１を用い、シール具４０，４１を金属部材１の拡開部１２の拡開壁面１３に押し付けることにより、金属部材１の開口１３ｘのシールを行うため、金属部材１とシール具４０，４１との境界領域のシール性を良好に確保することができ、金属部材１の中空室１０の高圧化を効果的に達成することができ、金属部材１の壁１ａの膨出変形性を高めることができる。
【００５２】
なお本実施例によれば、焼入後において、金属部材１の両端部の拡開部１２は不必要であれば、拡開部１２を切断により除去しても良いし、あるいは、拡開部１２が必要であれば残すことにしても良い。
【００５３】
（第２実施例）
以下、本発明の第２実施例について図４及び図５を参照して具体的に説明する。本実施例は、第１実施例と基本的には同様の構成を有し、基本的には同様の作用効果を奏する。以下、第１実施例と相違する部分を中心として説明する。本実施例は、第１実施例と同様に、代表的な急冷強化である焼入強化を金属部材１に対して行う例である。本実施例に係る金属部材１は、中空室１０を有する筒形状をなしており、焼入可能な鉄系金属で形成されている。鉄系金属は高強度化のためハイテン化（高張力鋼化）されており、塑性変形性は必ずしも充分ではない。
【００５４】
まず加熱工程では、成形型３の成形型面３１に金属部材１の壁１ａが対面するように、金属部材１を成形型３内に配置（装填）する。この場合、成形型３の成形型面３１に金属部材１の壁１ａの強化部位が接触しないように、金属部材１を配置することが好ましい。そして図４に示すように、金属部材１の中空室１０内に誘導加熱用のコイル状の導電部材６を配置する。即ち、成形型３の成形型面３１に対面する金属部材１に誘導加熱用の導電部材６を接近させる。この加熱工程では、成形型３の昇温を防止すると共に金属部材１の温度低下を防止するため、成形型３と金属部材１とを非接触状態にしておくことが好ましい。
【００５５】
上記したように金属部材１の中空室１０内に誘導加熱用の導電部材６を接近させて配置した状態で、導電部材６に高周波の交番電流を通電して金属部材１を誘導加熱する。導電部材６に通電する交番電流としては、金属部材１の壁１ａのうち強化要請部分をＡ１変態点以上またはＡ３変態点以上の温度領域に誘導加熱できる周波数及び電流値とする。このように導電部材６に高周波の交番電流を通電して金属部材１の壁１ａを誘導加熱する場合には、金属部材１の壁１ａのうち導電部材６に近接している表層を効率よく加熱できる近接効果と、金属部材１の表層を電流が流れる表皮効果とを期待できるため、金属部材１の壁１ａの表層を効率的に加熱することができる。このような誘導加熱の結果、金属部材１の組織の全部または一部は短時間にオーステナイト化される。
【００５６】
本実施例によれば、金属部材１を誘導加熱する加熱工程において成形型３の成形型面３１の温度上昇を抑えるため、必要に応じて、図４に示すように成形型３の成形型面３１と金属部材１との間に伝熱遮断部材９を配置することができる。伝熱遮断部材９としては、断熱性が高く、且つ、磁束遮断性が高いものが好ましい。なお、上記した加熱工程の前にまたは加熱工程の途中において、冷却水や冷媒ガス等の冷却媒体を成形型３の冷却通路３３に流して成形型３を冷却しておくことが好ましい。
【００５７】
次に、加熱工程を終えたら、伝熱遮断部材９を用いている場合には、伝熱遮断部材９を成形型３から離脱させる。上記した加熱工程を終えたら、成形急冷強化工程を行う。即ち、成形型３の成形型面３１を金属部材１に近づける。この場合、図５に示すように金属部材１の壁１ａと成形型面３１との間には空間Ｗが介在している。更に、第１実施例の場合と同様に、図５に示すように、金属部材１の拡開壁面１３の傾斜に対応する傾斜を有するシール具４０，４１を用い、シール具４０，４１を金属部材１の拡開壁面１３に直接的に、あるいは、中間部材を介して間接的にあてがってシールする。
【００５８】
このようにシール具４０，４１を金属部材１の拡開部１２の拡開壁面１３にシールした状態で、開閉弁５１を開放することにより、高圧気体供給源５のボンベ５０の高圧の気体を供給管５４及びシール具４０の通路４０ａを経て金属部材１の中空室１０に供給する。これにより金属部材１の中空室１０の気体の内圧を高め、金属部材１の壁１ａをこれの径方向の外方に膨出変形（塑性変形）させ、成形型３の成形型面３１に密接させる。これにより金属部材１の壁１ａを成形型３の成形型面３１に沿って成形し、成形急冷強化工程を行う。
【００５９】
なお、本実施例に係る成形急冷強化工程の直前または途中の段階において、焼入性を高めるべく、冷却水や冷媒ガス等の冷却媒体を成形型３の冷却通路３３に流して成形型３を冷却することが好ましい。
【００６０】
以上説明したように本実施例によれば、第１実施例の場合と同様に、金属部材１はハイテン化（高張力鋼化）されており、塑性変形性は必ずしも充分ではない鉄系金属で形成されているといえども、膨出変形の際に金属部材１は高温領域に加熱されているため、金属部材１の塑性変形性を向上させ、金属部材１の膨出変形性、ひいては成形性を高めることができる。
【００６１】
また本実施例によれば、成形急冷強化工程では、焼入温度以上に誘導加熱した金属部材１の壁１ａを膨出変形させて成形型３の成形型面３１に密接させることにより、金属部材１の壁１ａを焼入し、これにより金属部材１を強化させることができる。従って本実施例によれば、第１実施例の場合と同様に、金属部材１の壁１ａの成形性及び高強度化の双方を同時に達成することができる。
【００６２】
更に本実施例によれば、成形型３の成形型面３１に対面する金属部材１の壁１ａに誘導加熱用の導電部材６を接近させた状態で、導電部材６に高周波の交番電流を通電して金属部材１を誘導加熱する。このため金属部材１の壁１ａを目標温度領域に加熱した直後に開閉弁５１を開放して、高圧気体供給源５のボンベ５０の高圧の気体を金属部材１の中空室１０に供給し、金属部材１の壁１ａを膨出変形させて成形することができる。このため目標温度領域に加熱した金属部材１を加熱炉２から取り出して成形型３まで搬送する工程を廃止することができ、金属部材１の温度低下を抑えることができる。故に、金属部材１の成形直前及び焼入直前には、金属部材１の壁１ａの温度をできるだけ高温に維持することができ、金属部材１の成形及び焼入の双方を良好に行うことができる。
【００６３】
また本実施例によれば、金属部材１の壁１ａが成形型３の成形型面３１に触れたときに、成形型３の成形型面３１による焼入強化を行うことができる。
【００６４】
なお本実施例によれば、金属部材１を加熱する加熱工程を実施した後に、シール具４０，４１を金属部材１の拡開壁面１３にあてがってシールすることにしているが、これに限らず、金属部材１を加熱する加熱工程途中において、あるいは、加熱工程の前に、シール具４０，４１を金属部材１の拡開壁面１３にあてがっておいても良い。
【００６５】
（第３実施例）
以下、本発明の第３実施例について図６及び図７を参照して具体的に説明する。本実施例は、第２実施例と基本的には同様の構成を有し、基本的には同様の作用効果を奏する。以下、第２実施例と相違する部分を中心として説明する。加熱工程では、成形型３の成形型面３１に金属部材１の壁１ａが対面するように、金属部材１を成形型３内に配置（装填）する。この場合、成形型３の成形型面３１に金属部材１の強化要請部位が接触しないように、金属部材１を配置することが好ましい。
【００６６】
そして金属部材１を抵抗加熱操作によりＡ１変態点以上またはＡ３変態点以上の温度領域に加熱する。即ち、図６に示すように、成形型３の成形型面３１に対面する金属部材１の端部である拡開部１２に通電端子７を接続し、その状態で、通電端子７から金属部材１に通電して金属部材１の壁１ａをジュール熱でＡ１変態点以上またはＡ３変態点以上の温度領域に加熱する。通電端子７は銅系、アルミニウム系、チタン系、鉄系等のような導電性の良好な金属で形成することができる。通電端子７から金属部材１に通電する電流としては直流でも良いし、交番電流（交流）でも良い。
【００６７】
通電端子７から金属部材１に通電する電流が交番電流である場合には、周波数としては低周波数の領域、中周波数の領域、高周波数の領域を必要に応じて採用することができる。なお、通電端子７から金属部材１に高周波の交番電流を通電する場合には、金属部材１の表層を電流が流れる表皮効果を期待できるため、金属部材１の壁１ａの表層を効率的に加熱することができる。
【００６８】
本実施例においても、成形急冷強化工程では、図７に示すように、金属部材１の拡開部１２の拡開壁面１３の傾斜に対応する傾斜を有するシール具４０，４１を用いる。そして、シール具４０，４１を金属部材１の拡開部１２の拡開壁面１３に直接的に、あるいは、中間部材を介して間接的にあてがってシールする。このようにシール具４０，４１を金属部材１の拡開壁面１３にシールした状態で、開閉弁５１を開放することにより、高圧気体供給源５のボンベ５０の高圧の気体を供給管５４及びシール具４０の通路４０ａを経て金属部材１の中空室１０に供給する。これにより金属部材１の中空室１０の気体の内圧を高め、金属部材１の壁１ａをこれの径方向の外方に膨出変形（塑性変形）させ、成形型３の成形型面３１に密接させる。これにより金属部材１の壁１ａが成形型面３１に沿って成形される。
【００６９】
以上説明したように本実施例によれば、第１実施例及び第２実施例の場合と同様に、膨出変形の際に金属部材１は高温領域に加熱されているため、金属部材１がハイテン化された鉄系金属で形成されているといえども、金属部材１の塑性変形性を向上させることができ、金属部材１の膨出変形性、成形性を高めることができる。
【００７０】
また本実施例によれば、成形急冷強化工程では、焼入温度以上に抵抗加熱した金属部材１の壁１ａを膨出変形させて成形型３の成形型面３１に密接させることにより、金属部材１の壁１ａを焼入し、金属部材１の壁１ａを強化させることができる。従って本実施例によれば、第１実施例の場合と同様に、金属部材１の壁１ａの成形性及び高強度化の双方を達成することができる。
【００７１】
更に本実施例によれば、成形型３の成形型面３１に対面する金属部材１に通電端子７を接続した状態で、通電端子７から金属部材１に通電して加熱する。このため金属部材１の壁１ａを加熱した直後に、高圧の気体を金属部材１の中空室１０に供給して金属部材１の壁１ａを膨出変形させることができる。このため目標温度領域に加熱した金属部材１を加熱炉２から取り出して成形型３まで搬送する工程を廃止することができ、金属部材１の温度低下を抑えることができる。故に、金属部材１の成形直前及び焼入直前の状態において、金属部材１の温度を高温に維持することができる。従って、加熱した金属部材１の温度降下を抑えつつ、金属部材１の成形及び焼入の双方を良好に行うことができる。
【００７２】
加えて本実施例によれば、加熱工程において成形型３の成形型面３１の温度上昇を抑えるため、必要に応じて、図６に示すように、成形型３の成形型面３１と金属部材１との間に伝熱遮断部材９を配置することができる。伝熱遮断部材９としては、断熱性が高く、且つ、磁束遮断性が高いものが好ましい。
【００７３】
（第４実施例）
以下、本発明の第４実施例について図８及び図９を参照して具体的に説明する。本実施例は、第２実施例と基本的には同様の構成を有し、基本的には同様の作用効果を奏する。以下、第２実施例と相違する部分を中心として説明する。本実施例においても、加熱工程では、成形型３の成形型面３１に金属部材１の強化要請部位が密接しないように、金属部材１を配置することが好ましい。この場合、成形型３の成形型面３１に金属部材１の壁１ａが対面している。
【００７４】
本実施例においても、金属部材１を抵抗加熱操作によりＡ１変態点以上またはＡ３変態点以上の温度領域に加熱する。即ち、図８に示すように、成形型３の成形型面３１に対面する金属部材１の端部である拡開部１２に通電端子７を接続し、その状態で、通電端子７から金属部材１に通電して金属部材１の壁１ａをジュール熱で加熱する。また金属部材１の中空室１０に誘導加熱用の導電部材６を配置し、導電部材６に高周波の交番電流を通電することにより、金属部材１の壁１ａを誘導加熱する。
【００７５】
このように本実施例によれば、金属部材１の加熱にあたり、通電端子７による通電抵抗加熱と、誘導加熱用の導電部材６による誘導加熱とを複合的に併用しているため、金属部材１を効率よく加熱することができる。殊に、金属部材１の壁１ａのうち、塑性加工度が最も高い部位、あるいは、焼入強化が最も要請される部位に、誘導加熱用の導電部材６を接近させるため、当該部位を効果的に高温領域に加熱することができ、当該部位における塑性変形性及び焼入性を高めることができる。なお、本実施例においても、図９から分かるように、第２実施例と同様の成形急冷強化工程が行われる。
【００７６】
（適用例）
図１０は適用例１を示す。適用例１では、出発材としての直状円筒形状の金属部材１Ｂを用い、この直状円筒形状の金属部材１Ｂに対して、上記した各実施例に係る加熱工程、成形急冷強化工程を実施している。図１１は適用例２を示す。適用例２では、機械プレス加工により予め曲成部１ｒを形成した出発材としての筒形状の金属部材１Ｃを用いる。更に金属部材１Ｃに対して、溝加工を施して溝１ｓを形成する。そして溝加工を施した金属部材１Ｃに対して、上記した各実施例に係る加熱工程、成形急冷強化工程を実施している。本発明に係る金属部材１としては、車両のサスペンション機構に使用されるビーム、サスペンションメンバー、または、バンパーに付設されるバンパーレインフォースに適用することができる。また、車両の前席と後席との間に配置されるセンターピラー自体、あるいは、センターピラーにあてがわれてセンターピラーを補強するセンターピラーレインフォースに適用することもできる。
【００７７】
（その他）
前記した第１実施例によれば、金属部材１の両端部には拡開部１２が形成されているが、拡開部１２を形成することなく、金属部材１の両端部にシール具４０，４１を取り付けることもできる。また金属部材の拡開部１２は、加熱前に形成する必要はなく、加熱後のシール時と同時に形成しても良い。前記した第１実施例によれば、シール具４０，４１のシール面４４は円錐面状に傾斜しているが、これに限らず、直筒形状でも良い。
【００７８】
第１実施例によれば、一方のシール具４０は高圧気体供給源５に接続される通路４０ａを有し、他方のシール具４１は密閉機能を有しているものの、高圧気体供給源５には接続されていない。これに限らず、他方のシール具４０にも、高圧気体供給源５に接続される通路を形成しても良い。この場合、金属部材１の両端部から高圧の気体が供給される。
【００７９】
また第１実施例によれば、高圧気体供給源５は、高圧気体が封入されたボンベ５０と、ボンベ５０を開閉する開閉弁５１を有するバルブ５２と、ボンベ５０に封入されている気体の圧力を検出する圧力計５３と、バルブ５２から導出された供給通路として機能する可撓性を有する供給管５４とを有するが、これに限らず、高圧状態の気体により瞬間的に金属部材１を膨出変形させるものでも良く、要するに、高圧気体供給源５は金属部材１の中空室１０に気体を供給して金属部材１を所望とする形状に膨出成形できるものであれば良い。
【００８０】
更に第１実施例によれば、金属部材１を構成する焼入前の鉄系金属はハイテン化（高張力鋼化）されており、引張強さ６００ＭＰａ（≒６０ｋｇｆ／ｍｍ2）以上の鉄系金属とされているが、これに限らず、金属部材を構成する材料は、通常の炭素鋼や合金鋼でも良く、要するに成形型３の成形型面３１により急冷強化できるものであれば良い。
【００８１】
また第１実施例によれば、金属部材１を加熱する加熱工程と、金属部材１の壁１ａを膨出変形させる成形急冷強化工程とを分けているが、これに限らず、場合によっては、成形急冷強化工程の途中段階において金属部材１を加熱しても良い。例えば、金属部材１の壁１ａを膨出変形させる成形急冷強化工程の初期段階または中期段階において、金属部材１を加熱することにしても良い。
【００８２】
図６に示す第３実施例によれば、金属部材１の端部に通電端子７を接続しているが、通電端子７の構造及び材質は適宜選択することができる。要するに通電端子７は金属部材１に通電してこれを抵抗加熱できるものであればよい。第３実施例によれば、通電端子７は金属部材１の端部に接続されているが、これに限らず、金属部材１の中間部位に接続されていても良い。
【００８３】
前記した第２実施例及び第３実施例によれば、金属部材１を加熱する加熱工程において、成形型３と金属部材１とを非接触にしているが、これに限らず、加熱工程において金属部材１の保持等のために、成形型３と金属部材１とを部分的に接触させておいても良い。その他、本発明は上記した実施例のみに限定されるものではなく、要旨を逸脱しない範囲内で適宜変更して実施できるものである。
【００８４】
（付記）上記した記載から次の技術的思想も把握できる。
（付記項１）中空室を有するハイテン化された鉄系金属で形成された筒形状をなす金属部材と、成形型面を有する成形型とを用い、急冷強化可能な温度領域に加熱した前記金属部材の中空室の気体の内圧を高めることにより、前記金属部材の壁を膨出変形させ、膨出変形させた前記金属部材の壁を成形型の成形型面に密接させて成形すると共に急冷強化させる成形急冷強化工程を実施することを特徴とする金属部材成形方法。この場合、ハイテン化された鉄系金属で形成された金属部材を、成形性を確保しつつ、更に一層強化させることができる。
（付記項２）中空室を有する筒形状をなす金属部材と、成形型面を有する成形型とを用い、急冷強化可能な温度領域に前記金属部材を加熱する加熱工程と、加熱した前記金属部材の中空室の気体の内圧を高めることにより、前記金属部材の壁を膨出変形させ、膨出変形させた前記金属部材の壁を成形型の成形型面に密接させて成形すると共に急冷強化させる成形急冷強化工程とを実施することを特徴とする金属部材成形方法。
（付記項３）車両のセンターピラーを補強するセンターピラーレインフォースとなると共に中空室を有する筒形状をなす金属部材と、成形型面を有する成形型とを用い、急冷強化可能な温度領域に加熱した前記金属部材の中空室の気体の内圧を高めることにより、前記金属部材の壁を膨出変形させ、膨出変形させた前記金属部材の壁を成形型の成形型面に密接させて成形すると共に急冷強化させる成形急冷強化工程を実施することを特徴とするセンターピラーレインフォースの成形方法。この場合、センターピラーレインフォースの成形性を確保しつつ、高強度化を図ることができ、車両の耐側面衝突性を高めることができる。
（付記項４）各請求項または各付記項において、金属部材の加熱は、金属部材を成形型の成形型面に対面させた状態で行われることを特徴とする金属部材成形方法。
【００８５】
【発明の効果】
本発明に係る金属部材成形方法によれば、急冷強化可能な温度領域に金属部材を加熱する。そして成形急冷強化工程では、金属部材の中空室の気体の内圧を高めることにより、金属部材の壁を膨出変形させ、膨出変形させた金属部材の壁を成形型の成形型面に密接させて成形すると共に急冷強化させる。膨出変形の際に金属部材は加熱されているため、金属部材の塑性変形性が向上し、金属部材の膨出変形性、ひいては成形性が高まる。更に成形急冷強化工程では、膨出変形させた金属部材の壁を成形型の成形型面に密接させることにより、金属部材は急冷強化される。従って金属部材の成形性及び高強度化の双方を達成することができる。
【００８６】
本発明に係る金属部材成形方法によれば、加熱工程における金属部材の加熱温度、金属部材の厚み、成形型の成形型面の冷却能を適宜調整すれば、金属部材の壁の厚み方向において、成形型の成形型面に対面して密接する一方の表層の冷却速度を、成形型の成形型面に背向する他方の表層の冷却速度よりも速くできる。換言すれば、金属部材の壁の厚み方向において、成形型の成形型面に対面して密接する一方の表層の冷却速度よりも、成形型の成形型面に背向する他方の表層の冷却速度を遅くできる。従って、金属部材の壁の厚み方向において、成形型の成形型面に対面して密接する一方の表層の焼入性を高めてその部分の高強度化を図りつつ、成形型の成形型面に背向する他方の表層の焼入性を抑えてその部分の靱性を高めることもできる。
【００８７】
本発明に係る金属部材成形方法によれば、金属部材を成形型内に保持した状態で、該金属部材の冷却、或いは加熱及び冷却等の熱処理、具体的に一例を挙げると焼入れを行って金属部材の表面等を強化することができる。したがって、本発明によれば、比較的成形が困難な金属部材についても、気体を用いた成形手段によって、該金属部材を容易に成形することができる上に、該金属部材の高強度化も効率良く達成される。
【図面の簡単な説明】
【図１】実施例１に係り、金属部材の両端部に拡開部を形成し、加熱炉の炉室に配置する過程を模式的に示す斜視図である。
【図２】実施例１に係り、加熱した金属部材を成形型に配置した状態を模式的に示す断面図である。
【図３】実施例１に係り、加熱した金属部材を成形型に配置した状態において、金属部材の中空室に気体を供給して金属部材の壁を膨出させている状態を模式的に示す断面図である。
【図４】実施例２に係り、成形型に対面する金属部材を加熱している状態を模式的に示す断面図である。
【図５】実施例２に係り、成形型に対面するように配置され且つ加熱された金属部材の中空室に気体を供給する直前の状態を模式的に示す断面図である。
【図６】実施例３に係り、成形型に対面する金属部材を加熱している状態を模式的に示す断面図である。
【図７】実施例３に係り、成形型に対面するように配置され且つ加熱された金属部材の中空室に気体を供給する直前の状態を模式的に示す断面図である。
【図８】実施例４に係り、成形型に対面する金属部材を加熱している状態を模式的に示す断面図である。
【図９】実施例４に係り、成形型に対面するように配置され且つ加熱された金属部材の中空室に気体を供給する直前の状態を模式的に示す断面図である。
【図１０】適用例１を示す斜視図である。
【図１１】適用例２を示す斜視図である。
【符号の説明】
図中、１は金属部材、１０は中空室、１ａは壁、２は加熱炉、３は成形型、３１は成形型面、３３は冷却通路（冷却手段）、５は高圧気体供給源（気体供給手段）、５０はボンベ、５１は開閉弁、６は導電部材、７は通電端子をそれぞれ示す。[0001]
BACKGROUND OF THE INVENTION
The present invention can improve the formability and strength of metal members. Metal member forming method About.
[0002]
[Prior art]
A hydroforming method is known as a metal member forming method. The hydroform method uses a metal member having a cylindrical shape having a hollow chamber and a mold having a molding die surface set to a target shape, and supplying water to the hollow chamber of the metal member. In this technique, the wall is bulged and deformed, and the wall of the bulged and deformed metal member is brought into close contact with the mold surface of the mold.
[0003]
[Problems to be solved by the invention]
According to the hydroform method described above, by supplying water to the hollow chamber of the metal member, the metal member wall can be swelled and deformed. There was a limit to satisfying both.
[0004]
Particularly in recent automobile parts, etc., it is required to reduce the thickness of the material in order to reduce the weight. However, if the thickness is reduced, the forming force when forming the metal member can be reduced. There is a limit to increasing the strength of the.
[0005]
In addition, when the material is iron-based, there is a demand for high-tensileness (high-tensile steel) by increasing the amount of alloy elements while reducing the thickness of the material for weight reduction. In this case, the strength of the metal member can be increased, but the elongation of the material is reduced, so the formability of the material is reduced, and cracks are generated when the metal member is bulged and deformed by the hydroform method. There is a risk.
[0006]
The present invention has been made in view of the above circumstances, and can achieve both formability and high strength of a metal member. Metal member forming method It is an issue to provide.
[0007]
[Means for Solving the Problems]
The metal member molding method according to the present invention includes a cylindrical metal member having a hollow chamber, and a molding die surface. And cooling means for cooling the mold surface The metal member is bulged and deformed by increasing the internal pressure of the gas in the hollow chamber of the metal member heated to a temperature range capable of rapid quenching using a mold having When the member wall is in close contact with the mold surface of the mold, At the same time by the mold surface cooled by the cooling means It is characterized by carrying out a forming and quenching strengthening step for quenching and strengthening.
[0008]
According to the metal member forming method of the present invention, first, the metal member is heated to a temperature region in which rapid cooling strengthening is possible. In the forming and quenching strengthening step, the wall of the metal member is bulged and deformed by increasing the internal pressure of the gas in the hollow chamber of the metal member. At this time, since the gas is contained in the hollow chamber of the metal member, the temperature of the metal member is maintained higher than in the case where water is contained in the hollow chamber of the metal member as in the hydroforming method. be able to.
[0009]
Further, according to the metal member forming method of the present invention, the wall of the metal member bulged and deformed as described above is formed in close contact with the forming die surface of the forming die and is rapidly strengthened by cooling. When the metal member is bulged and deformed in this manner, the metal member is heated to a temperature region in which rapid quenching can be strengthened, so that the elongation of the metal member can be ensured. Therefore, the plastic deformability of the metal member can be improved, and the bulge deformability and formability of the metal member can be improved.
[0010]
Furthermore, in the above-described forming and quenching strengthening step, the metal member is rapidly strengthened by bringing the wall of the bulging and deformed metal member into close contact with the forming surface of the forming die, and the strength of the metal member can be increased.
[0013]
Said Metal member forming method for metal member already described By By molding, both the moldability and high strength of the metal member are achieved.
[0014]
Further, the present invention provides a molding die loaded with a cylindrical metal member having a hollow chamber, gas supply means for supplying gas to the hollow chamber of the metal member heated in the molding die, And a cooling means for cooling the metal member loaded in the mold by cooling the mold. Implemented with . According to the said metal member shaping | molding apparatus, a deformation | transformation and cooling of a metal member are performed continuously within a shaping | molding die. That is, the metal member is continuously formed and heat-treated.
[0015]
Said The metal member forming apparatus further includes means for heating the metal member loaded in the mold. According to the metal member forming apparatus, the metal member is continuously heated, deformed and cooled in the forming die. That is, the metal member is continuously formed and heat-treated, and workability is improved.
[0016]
DETAILED DESCRIPTION OF THE INVENTION
According to the metal member shaping | molding method, metal member, and metal member shaping | molding apparatus which concern on this invention, at least one of the following embodiment is employable.
[0017]
-The metal member as a starting material has a cylindrical shape having a hollow chamber. A cylindrical shape or a rectangular tube shape can be adopted as the cylindrical shape. As a metal member before performing a shaping | molding quenching strengthening process, a straight cylindrical shape may be sufficient, and the cylindrical shape which has at least one of a bending part, a recessed part, and a convex part may be sufficient. The metal member may be an integrally molded product or may be obtained by joining a plurality of materials.
[0018]
Embodiments that are iron-based (including alloy steels such as high-tensile steel and stainless steel), titanium-based, aluminum-based, or copper-based can be employed as the material of the metal member. However, it is not limited to these. High-tensile steel means high-tensile steel formed from steel with high tensile strength. As high-tensile steel, the tensile strength is 500 MPa (≈50 kgf / mm) before the forming and quenching strengthening step. 2 ) Adopt the above iron-based metals, iron-based metals with a tensile strength of 600 MPa or more, iron-based metals with a tensile strength of 800 MPa or more, iron-based metals with a tensile strength of 1000 MPa or more, and iron-based metals with a tensile strength of 1500 MPa or more. Can do. In general, high strength steel has high strength, but plastic deformation is not always sufficient. According to the method and the device of the present invention, these metal members are heated prior to the rapid cooling strengthening, so that the plastic deformability of the metal members is improved. For this reason, even when the plastic deformability is not always sufficient as in the case where the material of the metal member is made of high tensile strength, the bulging deformability and formability of the metal member can be improved. Therefore, even when the molding shape of the metal member is irregular or when the molding degree of the metal member is large, the moldability of the metal member can be ensured satisfactorily.
[0019]
The heating of the metal member employs an embodiment that is performed by at least one of an operation of holding the metal member in the furnace chamber of the heating furnace, an induction heating operation of induction heating of the metal member, and a resistance heating operation of energizing the metal member. can do. At least two of these operations can be used in combination. That is, after performing the operation of holding the metal member in the furnace chamber of the heating furnace, the induction heating operation of induction heating the metal member can be performed. Moreover, after performing operation which hold | maintains a metal member in the furnace chamber of a heating furnace, resistance heating operation which supplies with electricity to a metal member can be performed. Furthermore, the induction heating operation for induction heating of the metal member and the resistance heating operation for energizing the metal member can be performed without performing the operation of holding the metal member in the furnace chamber of the heating furnace. The induction heating operation for inductively heating the metal member and the resistance heating operation for energizing the metal member can be performed simultaneously in time or shifted in time.
[0020]
The embodiment in which the operation of holding the metal member in the furnace chamber of the heating furnace can be performed in a state where the furnace chamber of the heating furnace is in a non-oxidizing atmosphere. As the non-oxidizing atmosphere, at least one of a vacuum atmosphere, a reducing gas atmosphere, and an inert gas atmosphere can be employed. As the reducing gas atmosphere, at least one of a CO gas atmosphere and a gas atmosphere containing CO can be employed. As inert gas atmosphere, nitrogen gas atmosphere, rare gas atmospheres, such as argon gas, are employable.
[0021]
・ Induction heating operation for induction heating of metal members is performed by inducing an alternating current to the conductive member with the induction heating conductive member approaching the metal member facing the mold surface of the mold. Embodiments performed by heating can be employed. The conductive member for induction heating may be a coil shape or a plate shape, and in short, it is sufficient that the metal member can be induction heated. The frequency of the alternating current applied to the conductive member for induction heating can be appropriately selected in consideration of the material of the metal member, equipment cost, induction heating property, etc. within the frequency range in which the metal member can be induction heated. A low frequency region, a medium frequency region, and a high frequency region can be employed as necessary. As the frequency, for example, 0.5 kHz to 5000 kHz, particularly 1 kHz to 2000 kHz can be employed. However, it is not limited to these frequencies.
[0022]
In addition, when conducting a high frequency alternating current to the conductive member to inductively heat the metal member, the proximity effect that can efficiently heat the surface layer of the metal member close to the conductive member and the surface layer of the metal member Therefore, the surface layer of the metal member can be efficiently heated.
[0023]
-The resistance heating operation for energizing the metal member is performed by heating the metal member with Joule heat by energizing the metal member from the energizing terminal in a state where the energizing terminal is connected to the metal member facing the molding surface of the mold. The implemented embodiment can be employed. A direct current or an alternating current (alternating current) may be used as a current flowing from the energization terminal to the metal member. In the case of alternating current, considering the material of the metal member, equipment cost, resistance heating property, etc., the frequency range of low frequency, medium frequency, and high frequency is used as necessary. can do. As the frequency, for example, 0.5 kHz to 5000 kHz, particularly 1 kHz to 2000 kHz can be employed. However, it is not limited to these frequencies. When a high-frequency alternating current is applied to the metal member from the energization terminal, a skin effect in which current flows through the surface of the metal member can be expected, so that the surface of the metal member can be efficiently heated.
[0024]
The metal member is iron-based, and an embodiment in which the metal member is heated to a temperature region equal to or higher than the A1 transformation point (quenching temperature) can be employed. Above the A1 transformation point means a temperature range higher than the austenite generation temperature. In some cases, an embodiment in which heating is performed to a temperature range equal to or higher than the A3 transformation point may be employed. The upper limit of the heating temperature of the metal member is preferably the liquid phase generation temperature of the base material of the metal member.
[0025]
-In a shaping | molding quenching strengthening process, the wall of a metal member is closely_contact | adhered to the shaping | molding die surface of a shaping | molding die, and at least one part of a metal member can be hardened and martensitization can be promoted. By quenching in this way, the metal member can be strengthened. Further, in the case of rapid cooling strengthening, a form in which troostite, sorbite, or the like is generated together with or in place of martensite may be used. Trustite or sorbite tends to be generated when the cooling rate is slower than the cooling rate when martensite is generated.
[0026]
-When a metal member is an iron type, in order to improve hardenability, an alloy element with a high quenching multiple can be included. Examples of the alloy element having a high quenching multiple include carbon, manganese, silicon, nickel, chromium, and molybdenum, and can include at least one of these alloy elements. When the metal member is iron-based, the content of at least one of the above-described alloy elements (for example, carbon) is often increased in order to make the material high-tensile.
[0027]
-The shaping | molding die can employ | adopt embodiment provided with the cooling means to cool a shaping | molding die. As a cooling means, a cooling passage is formed inside the mold and a cooling medium such as cooling water or refrigerant gas is supplied to the cooling passage. A cooling medium such as cooling water or refrigerant gas is provided on the mold surface of the molding die. At least one of the contact methods can be employed. Examples of the material of the mold include metals having good thermal conductivity and good durability such as carbon steel and alloy steel.
[0028]
-According to the method and the device of the present invention, by increasing the internal pressure of the gas in the hollow chamber of the metal member, the wall of the metal member is bulged and deformed and brought into close contact with the mold surface of the mold. For the operation for increasing the internal pressure of the gas in the hollow chamber of the metal member, an embodiment can be adopted in which gas is supplied to the hollow chamber of the metal member. As the gas supplied to the hollow chamber of the metal member, at least one of air, nitrogen gas, nitrogen-enriched gas, argon gas, and argon-enriched gas can be employed. Nitrogen-enriched gas refers to a gas with a high nitrogen concentration. Argon-enriched gas refers to a gas having a high concentration of argon gas.
[0029]
-As operation which supplies gas to the hollow chamber of a metal member, embodiment implemented from the high pressure gas supply source which can supply high pressure gas is employable. It is preferable that the pressure of the high-pressure gas is high considering the moldability of the metal member. As the pressure of the high-pressure gas, for example, 10 MPa or more, 15 MPa or more, 20 MPa or more, 30 MPa or more can be set, but considering practicality, 15 to 25 MPa, 17 to 23 MPa, 19 to 21 MPa, and 20 MPa are preferable. Examples of the high-pressure gas supply source include a cylinder and a factory air source.
[0030]
-The metal member can employ | adopt embodiment which has an opening formed by the expanded wall surface while communicating with a hollow chamber. In this case, an embodiment is adopted in which the sealing member having an inclination corresponding to the inclination of the expanded wall surface of the metal member is directly or indirectly applied to the expanded wall surface of the metal member to seal the opening of the metal member. Can do. In this case, since the sealing tool is applied to the expanded wall surface that forms the opening of the metal member, the sealing on the expanded wall surface that forms the opening of the metal member is favorably performed. Therefore, it is advantageous for increasing the pressure of the hollow chamber of the metal member.
[0031]
The metal member forming method includes a step of loading (arranging) the metal member into the mold, a step of heating the metal member loaded in the mold, and a gas in the hollow chamber of the metal member heated in the mold. To plastically deform the metal member and bring the predetermined surface of the metal member into close contact with the predetermined surface of the mold At the same time By cooling the mold with the metal member inserted in the mold Depending on the mold surface being cooled, Including cooling the metal member Form Can be adopted.
[0032]
In addition, the metal member forming method includes a step of heating the metal member, a step of loading (arranging) the heated metal member in the mold, and a step of filling the hollow chamber of the metal member loaded in the mold after the heating. By supplying gas, the metal member is plastically deformed, and the predetermined surface of the metal member is brought into close contact with the predetermined surface of the mold. At the same time By cooling the mold with the metal member inserted in the mold Depending on the mold surface being cooled, An embodiment including a step of cooling the metal member can be employed.
[0033]
The metal member having a desired shape is formed by any one of the metal member forming methods described above. When forming a metal member into a desired shape, it is possible to achieve both formability and high strength of the metal member by using any one of the above-described metal member forming methods. Become.
[0034]
As the metal member forming apparatus, a molding die loaded with a cylindrical metal member having a hollow chamber, a gas supply means for supplying gas to the hollow chamber of the metal member heated in the molding die, and a molding die are provided. An embodiment including cooling means for cooling the metal member loaded in the mold by cooling can be employed. As the gas supply means, the high-pressure gas supply source described above can be exemplified, and the high-pressure gas supply source includes a cylinder, a valve, a supply pipe, and the like.
[0035]
Further, the metal member forming apparatus including the forming die, the gas supply means, and the cooling means may have means for heating the metal member loaded in the forming die. In this case, examples of the means for heating the metal member include the induction heating operation and the resistance heating operation described above.
[0036]
【Example】
(First embodiment)
Hereinafter, a first embodiment of the present invention will be described in detail with reference to FIGS. The present embodiment is an example in which quenching strengthening, which is typical quench strengthening, is performed on the metal member 1 as a starting material. The metal member 1 used in the forming method according to the present embodiment has a cylindrical shape having a hollow chamber 10 and is formed of an iron-based metal. The iron-based metal before quenching is made high-tensile (high-tensile steel). Specifically, the tensile strength is 600 MPa (≈60 kgf / mm). 2 ) It is made of the above iron-based metal, and plastic deformability is not always sufficient.
[0037]
According to the present embodiment, as shown in FIG. 1, by expanding the both ends of the hollow metal member 1, the expanded portion 12 that expands toward the end 12 c is formed in advance. . An expanded wall surface 13 that is an inner wall surface of the expanded portion 12 forms an opening 13 x communicating with the hollow chamber 10.
[0038]
First, in the heating step, the metal member 1 is held in the furnace chamber 20 of the heating furnace 2 for a predetermined time, and the metal member 1 is heated to a temperature range in which quenching strengthening can be performed, that is, a temperature range equal to or higher than the A1 transformation point. In this case, the metal member 1 can be heated to a temperature region equal to or higher than the A3 transformation point as necessary. Thereby, all or a part of the structure of the metal member 1 is austenitized. Since the furnace chamber 20 of the heating furnace 2 is maintained in a non-oxidizing atmosphere, oxidation and decarburization of the metal member 1 being heated can be suppressed. As the non-oxidizing atmosphere, a vacuum atmosphere, a reducing gas atmosphere, an inert gas atmosphere such as argon gas, or the like can be employed as necessary.
[0039]
Next, the metal member 1 heated to the target temperature region as described above is taken out from the heating furnace 2, and the metal member 1 is placed (loaded) in the mold 3 as shown in FIG. The mold 3 is made of a steel material that is a typical metal material, and has a mold surface 31 set to a target shape. In this case, it is preferable to arrange the metal member 1 so that the strengthening request portion of the wall 1 a of the metal member 1 does not contact the mold surface 31 of the mold 3. Inside the mold 3, a cooling passage 33 through which a cooling medium such as cooling water or refrigerant gas flows is formed as a cooling means. When a cooling medium such as cooling water or refrigerant gas flows into the cooling passage 33, the molding die 3 is cooled, and the metal member 1 that is a molding object can be rapidly cooled by the molding die surface 31 of the molding die 3. Note that it is preferable to cool the molding die 3 by flowing a cooling medium such as cooling water or refrigerant gas through the cooling passage 33 of the molding die 3 before or during the heating step.
[0040]
In the forming and quenching strengthening step according to the present embodiment, as shown in FIG. 2, a set of two having a seal surface 44 having an inclination corresponding to the inclination of the expanded wall surface 13 of the expanded portion 12 of the metal member 1. Sealing tools 40 and 41 are used. The sealing devices 40 and 41 can be formed of metal or refractory. One sealing tool 40 has a passage 40a connected to a high-pressure gas supply source 5 as gas supply means. The other sealing device 41 has a sealing function, but is not connected to the high-pressure gas supply source 5. The high-pressure gas supply source 5 supplies high-pressure gas, and includes a cylinder 50 in which high-pressure gas is sealed, a valve 52 having an opening / closing valve 51 for opening and closing the cylinder 50, and the pressure of the gas sealed in the cylinder 50. A pressure gauge 53 that functions as a pressure detecting means for detecting the pressure, and a flexible supply pipe 54 that functions as a supply passage led out from the valve 52.
[0041]
As shown in FIG. 2, the sealing devices 40 and 41 are fitted into the openings 13 x at both ends of the metal member 1, and the seal surface 44 is directly or not shown on the expanded wall surface 13 of the expanded portion 12 of the metal member 1. The seal is applied indirectly through the intermediate member. In this case, a space W is interposed between the wall 1 a of the metal member 1 and the mold surface 31.
[0042]
In the forming and quenching strengthening process according to the present embodiment, the high pressure (for example, 20 MPa) of the high pressure gas supply source 5 is used in a state where the sealing devices 40 and 41 are sealed to the expanded wall surface 13 of the expanded portion 12 of the metal member 1 as described above. ) Is supplied to the hollow chamber 10 of the metal member 1. Specifically, by opening the on-off valve 51 of the high-pressure gas supply source 5, the high-pressure gas in the cylinder 50 of the high-pressure gas supply source 5 is supplied to the metal member 1 through the supply pipe 54 and the passage 40 a of one seal tool 40. The hollow chamber 10 is supplied.
[0043]
As a result, the internal pressure of the gas in the hollow chamber 10 of the metal member 1 is increased, the wall 1a of the metal member 1 is bulged and deformed (plastically deformed) outward in the radial direction, and is closely attached to the mold surface 31 of the mold 3 Let As shown in FIG. 3, the wall 1 a of the metal member 1 is thereby molded along the mold surface 31. Further, simultaneously with the molding, the wall 1a of the metal member 1 is quenched by the molding surface 31 of the molding die 3, so that the wall 1a of the metal member 1 is quenched.
[0044]
Immediately before or during the molding quenching strengthening process according to this embodiment, a cooling medium such as cooling water or refrigerant gas is allowed to flow through the cooling passage 33 of the mold 3 to cool the mold 3 in order to improve hardenability. It is preferable.
[0045]
As the gas supplied to the hollow chamber 10 of the metal member 1, at least one of air, nitrogen gas, nitrogen-enriched gas, argon gas, and argon-enriched gas can be employed as necessary. In consideration of cost reduction, air can be employed. Considering oxidation suppression of the metal member 1, nitrogen gas, nitrogen-enriched gas, argon gas, or argon-enriched gas having low or no oxidizing ability can be employed. In addition, when shaping | molding and hardening of the metal member 1 are complete | finished as mentioned above, while separating the metal member 1 and the sealing tools 40 and 41, the metal member 1 provided with the desired shape is removed from the shaping | molding die 3. Separate.
[0046]
As described above, according to this embodiment, since the metal member 1 is heated to a high temperature region during the bulging deformation, the material constituting the metal member 1 is formed of a high-tensile metal material and is plastic. Even though the deformability is lowered, the plastic deformability of the metal member 1 can be improved. For this reason, the bulging deformability of the metal member 1 and thus the formability can be improved.
[0047]
Furthermore, according to the present embodiment, in the forming and quenching strengthening step, the wall 1a of the bulging and deforming metal member 1 is brought into close contact with the forming die surface 31 of the forming die 3, thereby depriving the wall 1a of the metal member 1 with heat. The wall 1a of the metal member 1 can be hardened. Thereby, the wall 1a of the metal member 1 can be strengthened. That is, as described above, according to the present embodiment, both the formability and the high strength of the wall 1a of the metal member 1 can be achieved at the same time.
[0048]
Thus, according to this example in which the metal member 1 can be reinforced, the tensile strength is 600 MPa (≈60 kgf / mm before quenching). 2 ) Despite the use of the metal member 1 formed of the above iron-based metal, the tensile strength of 1000 MPa (≈100 kgf / mm) is obtained by quenching the iron-based metal constituting the metal member 1 by the above-described quenching. 2 ) Or 1200 MPa or more, and in some cases 1500 MPa or more.
[0049]
According to the present embodiment, as described above, in the forming and quenching strengthening step, the wall 1a of the metal member 1 that has been bulged and deformed is brought into close contact with the forming die surface 31 of the forming die 3 so that the wall 1a of the metal member 1 is in contact. It is decided to strengthen the quenching. Therefore, if the heating temperature of the metal member 1 in the heating process and the cooling ability of the mold surface 31 of the mold 3 are appropriately adjusted, the mold member 31 faces the mold surface 31 of the mold 3 in the thickness direction of the wall 1a of the metal member 1. Thus, the cooling rate of one surface layer 1c (outer surface layer) in close contact can be made faster than the cooling rate of the other surface layer 1d (inner surface layer) facing away from the mold surface 31 of the mold 3.
[0050]
In other words, in the thickness direction of the wall 1 a of the metal member 1, the mold surface of the mold 3 is faster than the cooling rate of one surface layer 1 c (outer surface layer) that is in close contact with the mold surface 31 of the mold 3. The cooling rate of the other surface layer 1d (inner surface layer) facing away from the surface 31 can be reduced. Therefore, in the thickness direction of the wall 1a of the metal member 1, the hardenability of the one surface layer 1c (outer surface layer) that is in close contact with the mold surface 31 of the mold 3 is increased to increase the strength of this portion. In addition, the hardenability of the other surface layer 1d (inner surface layer) facing away from the mold surface 31 of the mold 3 can be suppressed to ensure the toughness of this portion. That is, the degree of quenching strengthening can be changed in the thickness direction of the wall 1a of the metal member 1, and the effect of increasing both the strength and impact resistance of the metal member 1 can be expected.
[0051]
In addition, according to the present embodiment, the sealing devices 40 and 41 having the sealing surface 44 having the inclination corresponding to the inclination of the expanding wall surface 13 of the expanding portion 12 of the metal member 1 are used. Since the opening 13x of the metal member 1 is sealed by being pressed against the expanded wall surface 13 of the expanded portion 12 of the metal member 1, the sealing performance in the boundary region between the metal member 1 and the sealing devices 40 and 41 is ensured satisfactorily. Therefore, the high pressure of the hollow chamber 10 of the metal member 1 can be effectively achieved, and the bulging deformability of the wall 1a of the metal member 1 can be enhanced.
[0052]
According to the present embodiment, after the quenching, if the expanded portions 12 at both ends of the metal member 1 are unnecessary, the expanded portions 12 may be removed by cutting, or the expanded portions. 12 may be left if necessary.
[0053]
(Second embodiment)
Hereinafter, a second embodiment of the present invention will be described in detail with reference to FIGS. This embodiment has basically the same configuration as the first embodiment, and basically has the same operational effects. In the following, the description will be focused on the differences from the first embodiment. In the present embodiment, similar to the first embodiment, quenching strengthening, which is a typical quench strengthening, is performed on the metal member 1. The metal member 1 according to the present embodiment has a cylindrical shape having a hollow chamber 10 and is formed of a hardenable iron-based metal. Iron-based metals are high-tensile (high-tensile steel) for high strength, and plastic deformability is not always sufficient.
[0054]
First, in the heating step, the metal member 1 is placed (loaded) in the mold 3 so that the wall 1 a of the metal member 1 faces the mold surface 31 of the mold 3. In this case, it is preferable to arrange the metal member 1 so that the reinforcing part of the wall 1 a of the metal member 1 does not contact the mold surface 31 of the mold 3. Then, as shown in FIG. 4, a coiled conductive member 6 for induction heating is disposed in the hollow chamber 10 of the metal member 1. That is, the induction heating conductive member 6 is brought close to the metal member 1 facing the mold surface 31 of the mold 3. In this heating step, it is preferable to keep the mold 3 and the metal member 1 in a non-contact state in order to prevent the mold 3 from rising in temperature and to prevent the temperature of the metal member 1 from decreasing.
[0055]
As described above, in a state where the conductive member 6 for induction heating is placed close to the hollow chamber 10 of the metal member 1, a high frequency alternating current is passed through the conductive member 6 to inductively heat the metal member 1. As an alternating current for energizing the conductive member 6, a frequency and a current value that can be induction-heated in a temperature range above the A1 transformation point or above the A3 transformation point in the wall 1 a of the metal member 1. As described above, when the high-frequency alternating current is applied to the conductive member 6 to inductively heat the wall 1a of the metal member 1, the surface layer of the metal member 1 adjacent to the conductive member 6 is efficiently heated. Since the proximity effect that can be performed and the skin effect in which a current flows through the surface layer of the metal member 1 can be expected, the surface layer of the wall 1a of the metal member 1 can be efficiently heated. As a result of such induction heating, all or part of the structure of the metal member 1 is austenitized in a short time.
[0056]
According to the present embodiment, in order to suppress the temperature rise of the mold surface 31 of the mold 3 in the heating process of induction heating the metal member 1, the mold surface of the mold 3 as shown in FIG. The heat transfer blocking member 9 can be disposed between the metal member 1 and the metal member 1. As the heat transfer blocking member 9, a member having high heat insulating properties and high magnetic flux blocking properties is preferable. Note that it is preferable to cool the molding die 3 by flowing a cooling medium such as cooling water or refrigerant gas through the cooling passage 33 of the molding die 3 before or during the heating step.
[0057]
Next, when the heating step is finished, when the heat transfer blocking member 9 is used, the heat transfer blocking member 9 is detached from the mold 3. When the heating step described above is completed, a forming and quenching strengthening step is performed. That is, the mold surface 31 of the mold 3 is brought close to the metal member 1. In this case, as shown in FIG. 5, a space W is interposed between the wall 1 a of the metal member 1 and the mold surface 31. Further, as in the case of the first embodiment, as shown in FIG. 5, seal tools 40 and 41 having an inclination corresponding to the inclination of the expanded wall surface 13 of the metal member 1 are used, and the seal tools 40 and 41 are made of metal. The seal is applied directly to the expanded wall surface 13 of the member 1 or indirectly via an intermediate member.
[0058]
In the state where the sealing devices 40 and 41 are sealed to the expanded wall surface 13 of the expanded portion 12 of the metal member 1, the high-pressure gas in the cylinder 50 of the high-pressure gas supply source 5 is released by opening the on-off valve 51. It is supplied to the hollow chamber 10 of the metal member 1 through the supply pipe 54 and the passage 40 a of the seal tool 40. As a result, the internal pressure of the gas in the hollow chamber 10 of the metal member 1 is increased, the wall 1a of the metal member 1 is bulged and deformed (plastically deformed) outward in the radial direction, and is closely attached to the mold surface 31 of the mold 3 Let As a result, the wall 1a of the metal member 1 is formed along the forming surface 31 of the forming die 3, and the forming and quenching strengthening step is performed.
[0059]
Note that, immediately before or during the molding quenching strengthening step according to the present embodiment, a cooling medium such as cooling water or refrigerant gas is allowed to flow through the cooling passage 33 of the molding die 3 in order to improve hardenability. It is preferable to cool.
[0060]
As described above, according to this embodiment, as in the case of the first embodiment, the metal member 1 is made of high-tensile steel (high-tensile steel) and is not necessarily necessarily sufficient in plastic deformation. Even though it is formed, the metal member 1 is heated to a high temperature region during the bulging deformation, so that the plastic deformability of the metal member 1 is improved, and the bulging deformability of the metal member 1 and thus the formability. Can be increased.
[0061]
Further, according to the present embodiment, in the forming and quenching strengthening step, the wall 1a of the metal member 1 that has been induction-heated to the quenching temperature or more is bulged and deformed to be brought into close contact with the forming die surface 31 of the forming die 3, thereby 1 wall 1a can be hardened and the metal member 1 can be strengthened by this. Therefore, according to this embodiment, as in the case of the first embodiment, it is possible to simultaneously achieve both formability and high strength of the wall 1a of the metal member 1.
[0062]
Furthermore, according to the present embodiment, a high-frequency alternating current is applied to the conductive member 6 while the conductive member 6 for induction heating is brought close to the wall 1a of the metal member 1 facing the mold surface 31 of the mold 3. Then, the metal member 1 is induction-heated. For this reason, immediately after heating the wall 1a of the metal member 1 to the target temperature region, the on-off valve 51 is opened, and the high-pressure gas from the cylinder 50 of the high-pressure gas supply source 5 is supplied to the hollow chamber 10 of the metal member 1, The wall 1a of the member 1 can be formed by bulging and deforming. For this reason, the process which takes out the metal member 1 heated to the target temperature range from the heating furnace 2 and conveys it to the shaping | molding die 3 can be abolished, and the temperature fall of the metal member 1 can be suppressed. Therefore, immediately before forming the metal member 1 and immediately before quenching, the temperature of the wall 1a of the metal member 1 can be maintained as high as possible, and both the forming and quenching of the metal member 1 can be performed satisfactorily. .
[0063]
Further, according to the present embodiment, when the wall 1 a of the metal member 1 touches the mold surface 31 of the mold 3, the quenching strengthening by the mold surface 31 of the mold 3 can be performed.
[0064]
In addition, according to a present Example, after implementing the heating process which heats the metallic member 1, it is supposed that the sealing tools 40 and 41 will be applied to the expansion wall surface 13 of the metallic member 1, and will seal, but it is not restricted to this. The sealing members 40 and 41 may be applied to the expanded wall surface 13 of the metal member 1 during the heating step of heating the metal member 1 or before the heating step.
[0065]
(Third embodiment)
Hereinafter, a third embodiment of the present invention will be described in detail with reference to FIGS. The present embodiment has basically the same configuration as the second embodiment, and basically has the same operational effects. Hereinafter, a description will be given centering on the difference from the second embodiment. In the heating step, the metal member 1 is placed (loaded) in the mold 3 such that the wall 1 a of the metal member 1 faces the mold surface 31 of the mold 3. In this case, it is preferable to dispose the metal member 1 so that the strengthening request portion of the metal member 1 does not contact the mold surface 31 of the mold 3.
[0066]
Then, the metal member 1 is heated to a temperature region above the A1 transformation point or above the A3 transformation point by a resistance heating operation. That is, as shown in FIG. 6, the energizing terminal 7 is connected to the widened portion 12 that is the end of the metal member 1 facing the forming die surface 31 of the forming die 3, and in this state, the energizing terminal 7 is connected to the metal member. 1 is energized and the wall 1a of the metal member 1 is heated by Joule heat to a temperature region above the A1 transformation point or above the A3 transformation point. The current-carrying terminal 7 can be formed of a metal having good conductivity such as copper-based, aluminum-based, titanium-based, or iron-based. A direct current or an alternating current (alternating current) may be used as a current flowing from the energization terminal 7 to the metal member 1.
[0067]
When the current passed through the metal member 1 from the energizing terminal 7 is an alternating current, a low frequency region, a medium frequency region, and a high frequency region can be used as necessary. When a high-frequency alternating current is applied to the metal member 1 from the energization terminal 7, a skin effect can be expected in which a current flows through the surface layer of the metal member 1, so that the surface layer of the wall 1a of the metal member 1 is efficiently heated. can do.
[0068]
Also in the present embodiment, in the forming and quenching strengthening step, as shown in FIG. 7, seal tools 40 and 41 having an inclination corresponding to the inclination of the expanded wall surface 13 of the expanded portion 12 of the metal member 1 are used. And the sealing tools 40 and 41 are applied to the expansion wall surface 13 of the expansion part 12 of the metal member 1 directly or indirectly via an intermediate member, and are sealed. In the state where the sealing devices 40 and 41 are sealed to the expanded wall surface 13 of the metal member 1, the high-pressure gas in the cylinder 50 of the high-pressure gas supply source 5 is supplied to the supply pipe 54 and the seal by opening the on-off valve 51. It is supplied to the hollow chamber 10 of the metal member 1 through the passage 40a of the tool 40. As a result, the internal pressure of the gas in the hollow chamber 10 of the metal member 1 is increased, the wall 1a of the metal member 1 is bulged and deformed (plastically deformed) outward in the radial direction, and is closely attached to the mold surface 31 of the mold 3 Let As a result, the wall 1 a of the metal member 1 is formed along the mold surface 31.
[0069]
As described above, according to the present embodiment, as in the case of the first embodiment and the second embodiment, since the metal member 1 is heated to the high temperature region during the bulging deformation, the metal member 1 is Even though it is made of high-tensile iron-based metal, the plastic deformability of the metal member 1 can be improved, and the bulging deformability and formability of the metal member 1 can be improved.
[0070]
Further, according to the present embodiment, in the forming and quenching strengthening step, the metal member 1 is swelled and deformed so as to be brought into close contact with the forming die surface 31 of the forming die 3 by causing the wall 1a of the metal member 1 that has been resistance heated to the quenching temperature or higher. 1 wall 1a can be hardened and the wall 1a of the metal member 1 can be strengthened. Therefore, according to the present embodiment, both the formability and high strength of the wall 1a of the metal member 1 can be achieved as in the case of the first embodiment.
[0071]
Further, according to the present embodiment, the current-carrying terminal 7 is energized and heated from the current-carrying terminal 7 with the current-carrying terminal 7 connected to the metal member 1 facing the mold surface 31 of the mold 3. For this reason, immediately after heating the wall 1a of the metal member 1, a high-pressure gas can be supplied to the hollow chamber 10 of the metal member 1 to bulge and deform the wall 1a of the metal member 1. For this reason, the process which takes out the metal member 1 heated to the target temperature range from the heating furnace 2 and conveys it to the shaping | molding die 3 can be abolished, and the temperature fall of the metal member 1 can be suppressed. Therefore, the temperature of the metal member 1 can be maintained at a high temperature immediately before forming the metal member 1 and immediately before quenching. Therefore, both shaping | molding and hardening of the metal member 1 can be performed favorably, suppressing the temperature fall of the heated metal member 1. FIG.
[0072]
In addition, according to the present embodiment, in order to suppress the temperature rise of the mold surface 31 of the mold 3 in the heating step, as shown in FIG. 1 and the heat transfer blocking member 9 can be disposed. As the heat transfer blocking member 9, a member having high heat insulating properties and high magnetic flux blocking properties is preferable.
[0073]
(Fourth embodiment)
Hereinafter, the fourth embodiment of the present invention will be described in detail with reference to FIGS. The present embodiment has basically the same configuration as the second embodiment, and basically has the same operational effects. Hereinafter, a description will be given centering on the difference from the second embodiment. Also in the present embodiment, in the heating process, it is preferable to arrange the metal member 1 so that the reinforcement requesting portion of the metal member 1 is not in close contact with the mold surface 31 of the mold 3. In this case, the wall 1 a of the metal member 1 faces the mold surface 31 of the mold 3.
[0074]
Also in the present embodiment, the metal member 1 is heated to a temperature region above the A1 transformation point or above the A3 transformation point by resistance heating operation. That is, as shown in FIG. 8, the energizing terminal 7 is connected to the widened portion 12 that is the end portion of the metal member 1 facing the mold surface 31 of the mold 3, and in this state, the energizing terminal 7 is connected to the metal member. 1 is energized to heat the wall 1a of the metal member 1 with Joule heat. In addition, the conductive member 6 for induction heating is disposed in the hollow chamber 10 of the metal member 1, and the wall 1 a of the metal member 1 is induction-heated by energizing the conductive member 6 with a high-frequency alternating current.
[0075]
As described above, according to the present embodiment, when the metal member 1 is heated, the energizing resistance heating by the energizing terminal 7 and the induction heating by the conductive member 6 for induction heating are used in combination. Can be efficiently heated. In particular, in order to bring the conductive member 6 for induction heating close to the part of the wall 1a of the metal member 1 where the degree of plastic working is the highest or the part that is most required to be hardened, the part is effective. Can be heated to a high temperature region, and the plastic deformability and hardenability at the site can be improved. Also in this example, as can be seen from FIG. 9, the same forming and quenching strengthening process as in the second example is performed.
[0076]
(Application example)
FIG. 10 shows an application example 1. In Application Example 1, a straight cylindrical metal member 1B as a starting material is used, and the heating process and the forming and quenching strengthening process according to each of the above embodiments are performed on the straight cylindrical metal member 1B. ing. FIG. 11 shows a second application example. In Application Example 2, a cylindrical metal member 1C is used as a starting material in which the bent portion 1r is formed in advance by mechanical press processing. Further, the metal member 1C is grooved to form a groove 1s. And the heating process which concerns on each above-mentioned Example, and the shaping | molding quenching strengthening process are implemented with respect to 1 C of metal members which gave the groove process. The metal member 1 according to the present invention can be applied to a beam used in a vehicle suspension mechanism, a suspension member, or a bumper reinforcement attached to a bumper. Further, the present invention can be applied to the center pillar itself arranged between the front seat and the rear seat of the vehicle, or the center pillar reinforcement applied to the center pillar to reinforce the center pillar.
[0077]
(Other)
According to the first embodiment described above, the expanded portions 12 are formed at both ends of the metal member 1, but without forming the expanded portions 12, the sealing tool 40, 41 can also be attached. Further, the expanded portion 12 of the metal member does not need to be formed before heating, and may be formed at the same time as sealing after heating. According to the first embodiment described above, the sealing surfaces 44 of the sealing devices 40 and 41 are inclined in a conical shape, but the present invention is not limited to this, and a straight cylindrical shape may be used.
[0078]
According to the first embodiment, one sealing device 40 has a passage 40a connected to the high-pressure gas supply source 5, and the other sealing device 41 has a sealing function, but the high-pressure gas supply source 5 has Is not connected. The passage connected to the high-pressure gas supply source 5 may be formed not only in this but also in the other sealing tool 40. In this case, high-pressure gas is supplied from both ends of the metal member 1.
[0079]
According to the first embodiment, the high pressure gas supply source 5 includes the cylinder 50 in which the high pressure gas is sealed, the valve 52 having the opening / closing valve 51 for opening and closing the cylinder 50, and the pressure of the gas sealed in the cylinder 50. However, the present invention is not limited to this, and the metal member 1 is instantaneously expanded by a high-pressure gas. The high-pressure gas supply source 5 may be anything that can supply the gas to the hollow chamber 10 of the metal member 1 and bulge and form the metal member 1 into a desired shape.
[0080]
Further, according to the first embodiment, the iron-based metal before quenching constituting the metal member 1 is high-tensile (high-tensile steel) and has a tensile strength of 600 MPa (≈60 kgf / mm). 2 ) The above-mentioned iron-based metal is not limited to this, but the material constituting the metal member may be ordinary carbon steel or alloy steel, and in short, can be rapidly strengthened by the mold surface 31 of the mold 3. I need it.
[0081]
According to the first embodiment, the heating process for heating the metal member 1 and the forming and quenching strengthening process for bulging and deforming the wall 1a of the metal member 1 are not limited thereto. You may heat the metal member 1 in the middle stage of a shaping | molding quench strengthening process. For example, the metal member 1 may be heated in the initial stage or the middle stage of the forming and quenching strengthening process in which the wall 1a of the metal member 1 is bulged and deformed.
[0082]
According to the third embodiment shown in FIG. 6, the energizing terminal 7 is connected to the end of the metal member 1, but the structure and material of the energizing terminal 7 can be selected as appropriate. In short, the energizing terminal 7 may be anything that can energize the metal member 1 and resistance-heat it. According to the third embodiment, the energizing terminal 7 is connected to the end portion of the metal member 1, but is not limited thereto, and may be connected to an intermediate portion of the metal member 1.
[0083]
According to the second embodiment and the third embodiment described above, in the heating process for heating the metal member 1, the mold 3 and the metal member 1 are not in contact with each other. In order to hold the member 1, the mold 3 and the metal member 1 may be partially in contact with each other. In addition, the present invention is not limited to the above-described embodiments, and can be implemented with appropriate modifications within a range not departing from the gist.
[0084]
(Supplementary note) The following technical idea can be grasped from the above description.
(Additional Item 1) The metal heated to a temperature region capable of rapid quenching strengthening using a metal member having a cylindrical shape formed of a high-tensile iron-based metal having a hollow chamber and a mold having a mold surface By increasing the internal pressure of the gas in the hollow chamber of the member, the wall of the metal member is bulged and deformed, and the wall of the bulged and deformed metal member is formed in close contact with the mold surface of the mold and is rapidly cooled and strengthened. A method for forming a metal member, comprising performing a forming and quenching strengthening step. In this case, the metal member formed of the high-tensile iron-based metal can be further strengthened while ensuring formability.
(Additional Item 2) A heating step of heating the metal member in a temperature region capable of rapid quenching using a cylindrical metal member having a hollow chamber and a mold having a mold surface, and the heated metal member By increasing the internal pressure of the gas in the hollow chamber, the wall of the metal member is bulged and deformed, and the wall of the bulged and deformed metal member is formed in close contact with the mold surface of the mold and is rapidly strengthened by cooling. A method for forming a metal member, comprising performing a forming and quenching strengthening step.
(Additional Item 3) A center pillar reinforcement for reinforcing the center pillar of the vehicle and a metal member having a cylindrical shape having a hollow chamber and a mold having a mold surface are heated to a temperature range capable of rapid quenching strengthening. By increasing the internal pressure of the gas in the hollow chamber of the metal member, the wall of the metal member is bulged and deformed, and the wall of the bulged and deformed metal member is brought into close contact with the mold surface of the mold. A method of forming a center pillar reinforcement characterized by performing a forming and quenching strengthening step of rapidly strengthening together. In this case, it is possible to increase the strength while ensuring the formability of the center pillar reinforcement, and it is possible to improve the side collision resistance of the vehicle.
(Additional Item 4) In each claim or each additional item, the metal member is heated in a state where the metal member faces the forming die surface of the forming die.
[0085]
【The invention's effect】
According to the method for forming a metal member according to the present invention, the metal member is heated to a temperature range in which rapid strengthening is possible. In the forming and quenching strengthening step, by increasing the internal pressure of the gas in the hollow chamber of the metal member, the wall of the metal member is bulged and deformed, and the wall of the bulged and deformed metal member is brought into close contact with the mold surface of the mold. And rapidly strengthening. Since the metal member is heated during the bulging deformation, the plastic deformability of the metal member is improved, and the bulging deformability and thus formability of the metal member is improved. Further, in the forming and quenching strengthening step, the metal member is rapidly strengthened by bringing the wall of the bulging and deforming metal member into close contact with the forming die surface of the forming die. Therefore, both formability and high strength of the metal member can be achieved.
[0086]
According to the metal member molding method according to the present invention, if the heating temperature of the metal member, the thickness of the metal member, and the cooling ability of the mold surface of the mold are appropriately adjusted in the heating step, in the thickness direction of the wall of the metal member, The cooling rate of one surface layer that faces and closely contacts the mold surface of the mold can be made faster than the cooling rate of the other surface layer facing away from the mold surface of the mold. In other words, in the thickness direction of the wall of the metal member, the cooling rate of the other surface layer facing away from the mold surface of the mold is higher than the cooling rate of one surface layer facing and closely facing the mold surface of the mold. Can slow down. Therefore, in the thickness direction of the wall of the metal member, while improving the hardenability of one surface layer facing and closely facing the mold surface of the mold and increasing the strength of that portion, the mold surface of the mold It is also possible to suppress the hardenability of the other surface layer facing away and increase the toughness of that portion.
[0087]
Metal member forming method according to the present invention According to In the state where the metal member is held in the mold, the surface of the metal member can be strengthened by cooling the metal member, or heat treatment such as heating and cooling, specifically by quenching. Therefore, according to the present invention, even a metal member that is relatively difficult to form can be easily formed by gas forming means, and the strength of the metal member can be increased. Well achieved.
[Brief description of the drawings]
FIG. 1 is a perspective view schematically showing a process of forming widened portions at both ends of a metal member and arranging them in a furnace chamber of a heating furnace according to the first embodiment.
FIG. 2 is a cross-sectional view schematically showing a state in which a heated metal member is arranged in a mold according to the first embodiment.
FIG. 3 schematically shows a state in which a gas is supplied to the hollow chamber of the metal member to bulge the wall of the metal member in a state where the heated metal member is placed in the mold according to the first embodiment. It is sectional drawing.
4 is a cross-sectional view schematically showing a state where a metal member facing a forming die is heated according to the second embodiment. FIG.
FIG. 5 is a cross-sectional view schematically showing a state immediately before supplying a gas to a hollow chamber of a metal member which is arranged so as to face the mold and is heated according to the second embodiment.
FIG. 6 is a cross-sectional view schematically showing a state where a metal member facing a forming die is heated according to the third embodiment.
FIG. 7 is a cross-sectional view schematically showing a state immediately before supplying a gas to a hollow chamber of a metal member which is arranged so as to face the mold and is heated according to the third embodiment.
FIG. 8 is a cross-sectional view schematically showing a state where a metal member facing a forming die is heated according to the fourth embodiment.
FIG. 9 is a cross-sectional view schematically showing a state immediately before supplying gas to a hollow chamber of a metal member which is arranged to face a forming die and is heated according to Example 4;
10 is a perspective view showing an application example 1. FIG.
FIG. 11 is a perspective view showing an application example 2;
[Explanation of symbols]
In the figure, 1 is a metal member, 10 is a hollow chamber, 1a is a wall, 2 is a heating furnace, 3 is a mold, 31 is a mold surface, 33 is a cooling passage (cooling means), and 5 is a high-pressure gas supply source (gas). Supply means), 50 is a cylinder, 51 is an on-off valve, 6 is a conductive member, and 7 is an energizing terminal.

Claims (13)

中空室を有する筒形状をなす金属部材と、成形型面と該成形型面を冷却する冷却手段を有する成形型とを用い、
急冷強化可能な温度領域に加熱した前記金属部材の中空室の気体の内圧を高めることにより、前記金属部材の壁を膨出変形させ、膨出変形させた前記金属部材の壁を前記成形型の前記成形型面に密接させて成形すると同時に前記冷却手段によって冷却された前記成形型面によって急冷強化させる成形急冷強化工程を実施することを特徴とする金属部材成形方法。Using a cylindrical metal member having a hollow chamber, a molding die surface and a molding die having cooling means for cooling the molding die surface,
By increasing the internal pressure of the gas in the hollow chamber of the metal member heated to a temperature range in which rapid cooling strengthening is possible, the wall of the metal member is bulged and deformed, and the wall of the metal member that has been bulged and deformed is A metal member forming method characterized by performing a forming and quenching strengthening step in which forming is performed in close contact with the forming mold surface and at the same time quenching and strengthening is performed by the forming mold surface cooled by the cooling means . 請求項１において、前記金属部材の中空室の気体の内圧を高める操作は、前記金属部材の中空室に気体を供給することにより実行されることを特徴とする金属部材成形方法。  2. The metal member forming method according to claim 1, wherein the operation of increasing the internal pressure of the gas in the hollow chamber of the metal member is performed by supplying gas to the hollow chamber of the metal member. 請求項１または請求項２において、前記金属部材の加熱は、加熱炉の炉室に前記金属部材を保持する操作、前記金属部材を誘導加熱する誘導加熱操作、前記金属部材に通電する抵抗加熱操作の少なくとも１種で実行されることを特徴とする金属部材成形方法。  3. The heating of the metal member according to claim 1, wherein the metal member is heated by an operation of holding the metal member in a furnace chamber of the heating furnace, an induction heating operation of induction heating of the metal member, or a resistance heating operation of energizing the metal member. It is performed by at least 1 sort (s) of the metal member shaping | molding method characterized by the above-mentioned. 請求項３において、前記加熱炉の炉室に金属部材を保持する操作は、前記加熱炉の炉室を非酸化性雰囲気とした状態で実行されることを特徴とする金属部材成形方法。  4. The metal member forming method according to claim 3, wherein the operation of holding the metal member in the furnace chamber of the heating furnace is performed in a state where the furnace chamber of the heating furnace is in a non-oxidizing atmosphere. 請求項３において、前記金属部材を誘導加熱する前記誘導加熱操作は、前記成形型の前記成形型面に対面する前記金属部材に誘導加熱用の導電部材を接近させた状態で、前記導電部材に交番電流を通電して前記金属部材を誘導加熱することにより実行されることを特徴とする金属部材成形方法。  4. The induction heating operation according to claim 3, wherein the induction heating operation for induction heating the metal member is performed on the conductive member in a state in which the conductive member for induction heating is brought close to the metal member facing the mold surface of the mold. A method for forming a metal member, which is performed by passing an alternating current and induction heating the metal member. 請求項３において、前記金属部材に通電する前記抵抗加熱操作は、前記成形型の前記成形型面に対面する金属部材に通電端子を接続した状態で、前記通電端子から前記金属部材に通電して前記金属部材をジュール熱で加熱することにより実行されることを特徴とする金属部材成形方法。  4. The resistance heating operation for energizing the metal member according to claim 3, wherein the energization terminal is energized from the energization terminal to the metal member in a state where the energization terminal is connected to the metal member facing the mold surface of the mold. The metal member forming method is performed by heating the metal member with Joule heat. 請求項１〜請求項６のいずれか一項において、前記金属部材は鉄系、チタン系、アルミニウム系または銅系であることを特徴とする金属部材成形方法。  The metal member forming method according to claim 1, wherein the metal member is iron-based, titanium-based, aluminum-based, or copper-based. 請求項１〜請求項６のいずれか一項において、前記金属部材は鉄系であり、前記金属部材はＡ１変態点以上の温度に加熱され、前記成形急冷強化工程では、前記金属部材の壁を前記成形型の前記成形型面に密接させることにより前記金属部材の少なくとも一部を焼入することを特徴とする金属部材成形方法。  7. The metal member according to claim 1, wherein the metal member is iron-based, and the metal member is heated to a temperature equal to or higher than an A1 transformation point. A metal member forming method, comprising: quenching at least a part of the metal member by bringing the metal member into close contact with the surface of the mold. 請求項５又は６において、前記加熱操作は、前記成形型面と、前記金属部材との間に伝熱遮断部材を配置した状態で実行されることを特徴とする金属部材成形方法。The metal member forming method according to claim 5, wherein the heating operation is performed in a state where a heat transfer blocking member is disposed between the forming die surface and the metal member. 請求項１〜請求項９のいずれか一項において、前記金属部材の前記中空室に供給する気体は、空気、窒素ガス、窒素富化ガス、アルゴンガス、アルゴン富化ガスの少なくとも１種であることを特徴とする金属部材成形方法。  The gas supplied to the hollow chamber of the metal member according to any one of claims 1 to 9 is at least one of air, nitrogen gas, nitrogen-enriched gas, argon gas, and argon-enriched gas. A metal member forming method characterized by the above. 請求項２〜請求項１０のいずれか一項において、前記金属部材の前記中空室に気体を供給する操作は、高圧気体を供給できる高圧気体供給源から実行されることを特徴とする金属部材成形方法。  The metal member molding according to any one of claims 2 to 10, wherein the operation of supplying a gas to the hollow chamber of the metal member is performed from a high-pressure gas supply source capable of supplying a high-pressure gas. Method. 請求項１〜請求項１１のいずれか一項において、前記金属部材は、前記中空室に連通すると共に拡開壁面で形成された開口を有しており、前記拡開壁面の傾斜に対応する傾斜を有するシール具を、前記金属部材の前記拡開壁面に直接的にまたは間接的にあてがって前記開口をシールすることを特徴とする金属部材成形方法。  12. The metal member according to claim 1, wherein the metal member communicates with the hollow chamber and has an opening formed by an expanded wall surface, and corresponds to an inclination of the expanded wall surface. A metal member forming method, wherein the opening is sealed by directly or indirectly applying a sealing tool having the above to the expanded wall surface of the metal member. 請求項１〜請求項１２のいずれか一項において、前記金属部材の加熱の前または途中において、前記冷却手段により前記成形型面の冷却をしておくことを特徴とする金属部材成形方法。13. The metal member forming method according to claim 1, wherein the mold surface is cooled by the cooling means before or during the heating of the metal member.
JP2002043277A 2001-09-04 2002-02-20 Metal member forming method Expired - Fee Related JP3761820B2 (en)

Priority Applications (4)

Application Number Priority Date Filing Date Title
JP2002043277A JP3761820B2 (en) 2001-09-04 2002-02-20 Metal member forming method
US10/234,227 US20040040636A1 (en) 2001-09-04 2002-09-04 Metallic member forming method
GB0220482A GB2379180B (en) 2001-09-04 2002-09-04 Metallic member forming method
DE10240876A DE10240876B4 (en) 2001-09-04 2002-09-04 Method and device for forming a metal element

Applications Claiming Priority (4)

Application Number Priority Date Filing Date Title
JP2001-267550 2001-09-04
JP2001267550 2001-09-04
JP2002043277A JP3761820B2 (en) 2001-09-04 2002-02-20 Metal member forming method
US10/234,227 US20040040636A1 (en) 2001-09-04 2002-09-04 Metallic member forming method

Publications (2)

Publication Number Publication Date
JP2003154415A JP2003154415A (en) 2003-05-27
JP3761820B2 true JP3761820B2 (en) 2006-03-29

Family

ID=32685805

Family Applications (1)

Application Number Title Priority Date Filing Date
JP2002043277A Expired - Fee Related JP3761820B2 (en) 2001-09-04 2002-02-20 Metal member forming method

Country Status (4)

Country Link
US (1) US20040040636A1 (en)
JP (1) JP3761820B2 (en)
DE (1) DE10240876B4 (en)
GB (1) GB2379180B (en)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
KR20170007383A (en) 2014-06-19 2017-01-18 스미도모쥬기가이고교 가부시키가이샤 Molding System

Families Citing this family (45)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE102005030507B4 (en) * 2005-06-28 2008-04-03 Benteler Automobiltechnik Gmbh Door structure of a motor vehicle
DE102006015793C5 (en) * 2006-04-05 2009-02-12 Peter Dr.-Ing. Amborn Forming tool for forming hollow bodies or sheets by means of a pressurized gas or fluid
DE502007005635D1 (en) * 2006-12-13 2010-12-23 Univ Friedrich Alexander Er METHOD FOR HYDRO FORMING COMPONENTS
DE102007018395B4 (en) * 2007-04-17 2011-02-17 Benteler Automobiltechnik Gmbh Internal high-pressure forming
ES2332972B1 (en) * 2008-02-07 2011-01-31 Mondragon Goi Eskola Politeknikoa Jose Maria Arizmendiarrieta S.Coop HYDRAULIC DEVICE AND PROCEDURE FOR A HYDROCONFORMED DEVICE.
JP2009220141A (en) * 2008-03-14 2009-10-01 Marujun Co Ltd Method and apparatus for manufacturing pipe product
US20090242086A1 (en) * 2008-03-31 2009-10-01 Honda Motor Co., Ltd. Microstructural optimization of automotive structures
US20100170319A1 (en) * 2009-01-06 2010-07-08 Soren Wiberg Method for press hardening of metals
DE102009054558B4 (en) * 2009-12-11 2020-10-22 Robert Bosch Gmbh Device for autofrettage
DE102011102764B4 (en) * 2011-05-28 2024-08-08 Volkswagen Aktiengesellschaft Method for forming a shaft for torque transmission
KR101269718B1 (en) * 2011-06-28 2013-05-30 현대하이스코 주식회사 High strength steel parts using hydroforming
CN103648807B (en) * 2011-09-14 2017-03-29 株式会社威泰克 The manufacture method of hollow component and hollow component
CN102806248A (en) * 2012-08-06 2012-12-05 哈尔滨工业大学 Device and method for testing real-time changes of fillet radius along with internal pressure in internal high-pressure forming process
JP6326224B2 (en) 2013-12-09 2018-05-16 住友重機械工業株式会社 Molding equipment
JP6342667B2 (en) * 2014-02-10 2018-06-13 株式会社ワイテック Heat treatment method
EP3134217B1 (en) 2014-04-21 2021-11-17 Sumitomo Heavy Industries, Ltd. Hydroforming apparatus
JP6381967B2 (en) 2014-05-22 2018-08-29 住友重機械工業株式会社 Molding apparatus and molding method
JP6400952B2 (en) * 2014-06-18 2018-10-03 住友重機械工業株式会社 Molding system and molding method
JP6240564B2 (en) 2014-06-19 2017-11-29 住友重機械工業株式会社 Molding apparatus and method for replacing parts of molding apparatus
JP6475437B2 (en) 2014-08-05 2019-02-27 住友重機械工業株式会社 Molding equipment
CN104525676B (en) * 2014-12-08 2017-03-22 无锡朗贤汽车组件研发中心有限公司 Gas bulging hot formation segmentation strengthening process of boron steel tube
CN104525675B (en) * 2014-12-08 2017-03-22 无锡朗贤汽车组件研发中心有限公司 Gas bulging hot formation process of boron steel tube
JP6771271B2 (en) * 2015-03-31 2020-10-21 住友重機械工業株式会社 Molding equipment
JP2016190252A (en) * 2015-03-31 2016-11-10 住友重機械工業株式会社 Molding device
DE102015005522B4 (en) * 2015-04-30 2021-09-30 Schomäcker Federnwerk GmbH Method for producing a metallic hollow body
DE102015112327A1 (en) * 2015-07-28 2017-02-02 Benteler Automobiltechnik Gmbh Body or chassis component of a motor vehicle with improved crash performance and method for its production
JP6285082B2 (en) * 2015-08-27 2018-02-28 住友重機械工業株式会社 Molding apparatus and molding method
CA3015996C (en) * 2016-03-01 2023-12-12 Sumitomo Heavy Industries, Ltd. Forming device and forming method
JP6611180B2 (en) * 2016-03-31 2019-11-27 住友重機械工業株式会社 Molding equipment
DE102016114423A1 (en) * 2016-08-04 2018-02-08 Fraunhofer-Gesellschaft zur Förderung der angewandten Forschung e.V. Method and device for pressure forming hollow profiles
JP2018167284A (en) * 2017-03-29 2018-11-01 住友重機械工業株式会社 Metal body and electric conduction heating method
CN109926486B (en) * 2017-12-18 2020-02-07 哈尔滨工业大学 Ti2Method for hot-state air pressure forming and heat treatment of AlNb-based alloy hollow thin-wall component
CN108202098B (en) * 2018-03-02 2023-04-11 济南大学 Internal high pressure sealing push head
JP7080085B2 (en) * 2018-03-28 2022-06-03 住友重機械工業株式会社 Molding equipment
JP6875341B2 (en) * 2018-09-06 2021-05-26 住友重機械工業株式会社 Molding system and molding method
JP7158237B2 (en) * 2018-10-10 2022-10-21 住友重機械工業株式会社 Hollow structure and manufacturing method thereof
DE102019102638A1 (en) 2019-02-04 2020-08-06 Salzgitter Hydroforming GmbH & Co. KG Process for producing a metal component by means of hydroforming
EP3919201B1 (en) * 2019-03-04 2023-10-11 Intelligent Aerospace Manufacturing Technology (Beijing) Co., Ltd. Hot metal gas forming and quenching system and process therefor
CN110548799B (en) * 2019-09-10 2024-05-24 山东金润德新材料科技股份有限公司 Device and method for ultrahigh-pressure water expansion and vacuum auxiliary forming of clamping and pressing type pipe fitting
JP7023914B2 (en) * 2019-10-31 2022-02-22 住友重機械工業株式会社 Molding equipment
CN110976609B (en) * 2019-11-11 2021-02-19 潍坊倍力汽车零部件有限公司 Electric heating type sealing push head and metal forming process
US11338352B2 (en) * 2020-07-29 2022-05-24 Rheem Manufacturing Company Pressure expansion methods for heat exchanger manufacturing
CN112642916B (en) * 2020-12-01 2022-04-19 北京星航机电装备有限公司 Integrated forming die and forming method for large-reducing-ratio special-shaped titanium alloy thin-wall part
CA3237576A1 (en) * 2022-02-17 2023-08-24 Sumitomo Heavy Industries, Ltd. Electrical heating device, molding device, and electrical heating method
CN114798732B (en) * 2022-06-30 2022-10-21 太原理工大学 Method for regulating interface structure of bimetal laminated composite plate by multi-frequency composite current

Family Cites Families (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4584860A (en) * 1985-06-17 1986-04-29 Rockwell International Corporation Tooling system for superplastic forming of metals
SE9702058L (en) * 1997-05-30 1998-11-16 Accra Teknik Ab Process for making hardened metallic hollow bodies of thin-walled steel sheet by blow molding
US6322645B1 (en) * 1999-09-24 2001-11-27 William C. Dykstra Method of forming a tubular blank into a structural component and die therefor
DE10012974C1 (en) * 2000-03-16 2001-03-15 Daimler Chrysler Ag Production of a hollow profile used in the automobile industry comprises a cold forming a hollow profile green body, heating to a temperature above the austenite temperature

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
KR20170007383A (en) 2014-06-19 2017-01-18 스미도모쥬기가이고교 가부시키가이샤 Molding System
US10500627B2 (en) 2014-06-19 2019-12-10 Sumitomo Heavy Industries, Ltd. Forming system
EP3936322A1 (en) 2014-06-19 2022-01-12 Sumitomo Heavy Industries, Ltd. Forming system

Also Published As

Publication number Publication date
GB2379180B (en) 2004-01-07
GB2379180A (en) 2003-03-05
DE10240876B4 (en) 2006-02-23
DE10240876A1 (en) 2003-03-27
US20040040636A1 (en) 2004-03-04
JP2003154415A (en) 2003-05-27
GB0220482D0 (en) 2002-10-09
GB2379180A8 (en) 2003-03-18

Similar Documents

Publication Publication Date Title
JP3761820B2 (en) Metal member forming method
JP4316842B2 (en) Method for manufacturing tailored blank press molded products
Kolleck et al. Investigation on induction heating for hot stamping of boron alloyed steels
JP6075304B2 (en) Hot press molding method and hot press molding apparatus
US8691032B2 (en) Microstructural optimization of automotive structures
US7024897B2 (en) Method of forming a tubular blank into a structural component and die therefor
US7618503B2 (en) Method for improving the performance of seam-welded joints using post-weld heat treatment
CN101622365B (en) Method for improving the performance of seam-welded joints using post-weld heat treatment
EP3436207B1 (en) B-pillar with tailored properties
US20110315281A1 (en) Tailored Properties By Post Hot Forming Processing
CN106494175B (en) Stabilizer bar and process for manufacturing stabilizer bar
CN101018626B (en) Pressing forming device and pressing forming method for metal plate
CA2664912A1 (en) Microtreatment of iron-based alloy, apparatus and method therefor, and articles resulting therefrom
CN111107960A (en) Method for joining two blanks, and blank and product obtained
CN114262769A (en) Method for manufacturing a structural component comprising a thermomagnetic tempering process producing local soft zones
US20070063385A1 (en) Apparatus and method for sheet material forming
JP4724535B2 (en) Fatigue strength improvement method for high strength steel spot welded joint
CN110100016A (en) The method for manufacturing combined shaping component
CN111438327A (en) Mechanical connection method and device for automobile steel
US10266905B2 (en) Method and apparatus for hardening a component or semi-finished product
KR20140102873A (en) Hot gas blow forming steel pipe having high strength and method of manufacturing the same
US11332800B2 (en) Method and device for forming and hardening steel materials
US20200318211A1 (en) Method for Producing a Profiled Component, and Profiled Component
CN116550837A (en) Stamped part with reduced thermoforming cycle time
Pfaffmann et al. Hot metal gas forming of auto parts

Legal Events

Date Code Title Description
A977 Report on retrieval

Free format text: JAPANESE INTERMEDIATE CODE: A971007

Effective date: 20050412

A131 Notification of reasons for refusal

Free format text: JAPANESE INTERMEDIATE CODE: A131

Effective date: 20050419

A521 Request for written amendment filed

Free format text: JAPANESE INTERMEDIATE CODE: A523

Effective date: 20050617

TRDD Decision of grant or rejection written
A01 Written decision to grant a patent or to grant a registration (utility model)

Free format text: JAPANESE INTERMEDIATE CODE: A01

Effective date: 20060104

A61 First payment of annual fees (during grant procedure)

Free format text: JAPANESE INTERMEDIATE CODE: A61

Effective date: 20060111

R150 Certificate of patent or registration of utility model

Free format text: JAPANESE INTERMEDIATE CODE: R150

FPAY Renewal fee payment (event date is renewal date of database)

Free format text: PAYMENT UNTIL: 20130120

Year of fee payment: 7

FPAY Renewal fee payment (event date is renewal date of database)

Free format text: PAYMENT UNTIL: 20140120

Year of fee payment: 8

LAPS Cancellation because of no payment of annual fees