JP4273846B2

JP4273846B2 - Method and structure for joining thick materials

Info

Publication number: JP4273846B2
Application number: JP2003162459A
Authority: JP
Inventors: 久司堀; 勇人佐藤; 慎也牧田
Original assignee: Nippon Light Metal Co Ltd
Current assignee: Nippon Light Metal Co Ltd
Priority date: 2003-06-06
Filing date: 2003-06-06
Publication date: 2009-06-03
Anticipated expiration: 2023-06-06
Also published as: JP2004358535A

Description

【０００１】
【発明の属する技術分野】
本発明は、厚肉の被接合材同士を隙間なく接合する方法及び構造に関する。
【０００２】
【従来の技術】
特許文献１には、厚肉の被接合材同士を摩擦攪拌接合する方法が開示されている。その手順としては、まず図２１（Ａ）に示すように、一対の厚肉被接合材１，１の各接合端に、外側端面２ａと中間面２ｂと内側端面２ｃとからなる段部２を形成しておく。そして図２１（Ｂ）に示すように、これら一対の厚肉被接合材１，１の外側端面２ａ，２ａ同士を突き合わせて突合せ部３を形成し、この突合せ部３に沿って摩擦攪拌接合用のツール１０を挿入して摩擦攪拌接合を施すことにより、両厚肉被接合材１，１を接合して接合線Ｗ１を形成する。次に図２１（Ｃ）に示すように、両厚肉被接合材１，１の中間面２ｂ，２ｂと内側端面２ｃ，２ｃとで形成される凹部４に、この凹部４と同一又は相似の断面形状の接続板５を装入する。最後に図２１（Ｄ）に示すように、接続板５と各厚肉被接合材１，１の内側端面２ｃ，２ｃとの突合せ部６，６に沿って摩擦攪拌接合用のツール１０を挿入してそれぞれ摩擦攪拌接合を施すことにより、接合線Ｗ２，Ｗ２を形成する。このように、被接合材の厚さ方向に二段に分けて摩擦攪拌接合を施すことにより、既存の接合ツールでは対応できないような厚肉の被接合材を互いに接合することができる。
【０００３】
【特許文献１】
特許第３３０７３３０号公報（［００１３］−［００１８］，図１−２）
【０００４】
【発明が解決しようとする課題】
しかしながら、上記従来の方法によって接合された接合構造では、図２２に示したように、接続板５の底面と凹部４の底面（各厚肉被接合材１，１の中間面２ｂ，２ｂ）とが未接合のままで隙間８が残ってしまうことがある。また、接続板５と各厚肉被接合材１，１の内側端面２ｃ，２ｃとの突合せ部６を摩擦攪拌接合してなる接合線Ｗ２の内部に、ツールの進行方向に連続するトンネル状空洞欠陥９が残ってしまうことがある。そして、かかる隙間８やトンネル状空洞欠陥９は当該部分の気密性を低下させるので、この接合構造をたとえば半導体製造装置の真空処理容器等に用いた場合にはリークが発生しやすく、容器内を超高真空状態にして長時間保持することができないなどという問題がある。
【０００５】
本発明はかかる事情に鑑みてなされたものであり、厚肉の被接合材同士を隙間なく接合する厚肉被接合材の接合方法（以下、単に「接合方法」という。）及び厚肉被接合材の接合構造（以下、単に「接合構造」という。）を提案するものである。
【０００６】
すなわち、請求項１に係る発明は、それぞれの接合端に沿って外側端面と中間面と内側端面とを含む段部が形成された一対の厚肉被接合材の前記外側端面同士を突き合わせて、該突合せ部を摩擦攪拌接合する第一工程と、前記両厚肉被接合材の中間面と内側端面とで形成される凹部に、該凹部と同一又は相似の断面形状の接続板を装入する第二工程と、
前記接続板と前記各厚肉被接合材の内側端面との突合せ部をそれぞれ摩擦攪拌接合した後に、前記接続板と前記凹部の底面との境界面を摩擦攪拌する第三工程と、を含んでなる厚肉被接合材の接合方法であって、前記第三工程において、前記接続板と前記凹部の底面との境界面の摩擦攪拌を、前記接続板と前記各厚肉被接合材の内側端面との突合せ部を横断して施すことを特徴とする。
また、請求項２に係る発明は、それぞれの接合端に沿って外側端面と中間面と内側端面とを含む段部が形成された一対の厚肉被接合材の前記外側端面同士を突き合わせるとともに、前記両厚肉被接合材の中間面と内側端面とで形成される凹部に、該凹部と同一又は相似の断面形状の接続板を装入する第一工程と、前記一対の厚肉被接合材の外側端面同士を突き合わせてなる突合せ部と、前記接続板と前記各厚肉被接合材の内側端面との突合せ部と、についてそれぞれ摩擦攪拌接合を施した後に、前記接続板と前記凹部の底面との境界面を摩擦攪拌する第二工程と、を含んでなる厚肉被接合材の接合方法であって、前記第二工程において、前記接続板と前記凹部の底面との境界面の摩擦攪拌を、前記接続板と前記各厚肉被接合材の内側端面との突合せ部を横断して施すことを特徴とする。
さらに、請求項３に係る発明は、それぞれの接合端に沿って外側端面と中間面と内側端面とを含む段部が形成され、前記外側端面同士が突き合わされた一対の厚肉被接合材と、前記両厚肉被接合材の中間面と内側端面とで形成される凹部に装入された、該凹部と同一又は相似の断面形状の接続板と、を備え、前記両厚肉被接合材の外側面同士を突き合わせてなる突合せ部と、前記接続板と前記各厚肉被接合材の内側端面との突合せ部と、がそれぞれ摩擦攪拌接合された後に、前記接続板と前記凹部の底面との境界面が摩擦攪拌された厚肉被接合材の接合構造であって、前記接続板と前記凹部の底面との境界面の摩擦攪拌が、前記接続板と前記各厚肉被接合材の内側端面との突合せ部を横断して施されていることを特徴とする。
【０００７】
かかる接合方法ないし接合構造によれば、従来の接合方法ないし接合構造において未接合のまま残されていた、接続板と凹部の底面との境界面が摩擦攪拌により一体化されるので、当該部分の隙間をなくした気密性の高い接合部を形成することができる。
また、かかる接合方法ないし接合構造によれば、接続板と凹部の底面との境界面についての摩擦攪拌の前に、一対の厚肉被接合材の外側端面同士を突き合わせてなる突合せ部と、接続板と各厚肉被接合材の内側端面との突合せ部と、についての摩擦攪拌接合が完了しているので、摩擦攪拌時の接続板の位置決め・固定が容易である。
また、かかる接合方法ないし接合構造によれば、接続板と各厚肉被接合材の内側端面との突合せ部を横断して摩擦攪拌が施されるので、摩擦攪拌接合したときにトンネル状空洞欠陥が発生したとしても、このトンネル状空洞欠陥を分断して、気密性をさらに高めることができる。
【００１４】
【発明の実施の形態】
以下、添付図面を参照しつつ、本発明の実施の形態を詳細に説明する。なお、説明において、同一要素には同一の符号を用い、重複する説明は省略するものとする。また、厚肉被接合材として厚肉のアルミニウム板材を用い、且つ摩擦攪拌接合装置の接合能力が厚さ５ｍｍの場合を想定している。
【００１５】
＜第一実施形態＞
図１〜図４は本発明に係る接合方法の第一実施形態の各工程を表す断面図である。
まず、図１（Ａ）に示すように、接合すべき一対の厚肉被接合材１，１を、それぞれの外側端面２ａ，２ａで面接触させて突合せ部３を形成した上で、図示しない治具で拘束する。各厚肉被接合材１の厚さは５〜１０ｍｍであり、それぞれの接合端に沿って段部２が形成されている。段部２は、外側端面２ａと中間面２ｂと内側端面２ｃとを含んで形成されている。そして、一対の厚肉被接合材１，１の外側端面２ａ，２ａを互いに突き合わせたときに、連続する両中間面２ｂ，２ｂと、対向する一対の内側端面２ｃ，２ｃとで凹部４が形成される。なお、厚肉被接合材１にはアルミニウムの圧延板（ＡＡ５０５２合金、ＡＡ６０６１合金）を切削加工したものか、あるいは、段部２を予め一体に形成したアルミニウム（ＪＩＳ；Ａ６０６３−Ｔ５又はＴ６等）の押出形材が用いられる。
【００１６】
次に、図１（Ｂ）に示すように、突合せ部３上に、摩擦攪拌接合用のツール１０をセットする。このツール１０は、工具鋼からなり、回転円柱体１１と、その底面であって緩く湾曲して凹んだ表面押え部１２の中心から同軸にて垂下する攪拌ピン１３とからなる。この攪拌ピン１３は、厚肉被接合材１の外側端面２ａや内側端面２ｃの高さより若干短く、その周面には、図示しないネジ状の小さな摩擦攪拌翼が形成されている。そして、図１（Ｃ）及び（ｃ）に示すように、回転円柱体１１と攪拌ピン１３の中心軸を各厚肉被接合材１，１の突合せ部３に沿ってやや斜めにした状態で、図示しないモータによりツール１０を回転させつつ突合せ部３に向けて進入させる。ツール１０の回転速度は３００〜５０００ｒｐｍの範囲内において適宜選択される。なお、厚肉被接合材１，１は予め互いに長手方向及び幅方向に移動しないように拘束されている。
【００１７】
次いで、図示のように、ツール１０を各厚肉被接合材１に対し垂直方向に押圧し、表面押え部１２全体が中間面２ｂ，２ｂの表面に達するまで攪拌ピン１３を押し込む。この状態で、ツール１０をその傾斜した向きと反対方向に（図１（ｃ）で左方）に移動させる。この送り速度は、０．０２〜２ｍ／分の範囲内において適宜選択される。このツール１０の回転と移動に伴って、突合せ部３付近のメタルは攪拌ピン１３により加熱され可塑化されると共に、突合せ部３の左右の厚肉被接合材１，１間において水平及び垂直方向に流動化される。
【００１８】
また、流動化されたメタルは、ツール１０の表面押え部１２により垂直方向の流動に対し一定の圧力を与えられると共に、突合せ部３の表面付近から外部に飛散することを阻止される。この結果、図１（Ｄ），（ｄ）に示すように、ツール１０が通過した後において、流動化されたメタルは、流動化状態から固化して断面略半楕円形の接合線Ｗ１となる。この接合線Ｗ１の表面は、表面押え部１２により、その直径の幅相当分が僅かに凹むが、突合せ部３に沿って所要の長さで連続し、且つ表面が平らな接合線Ｗ１となる。
【００１９】
次いで、図２（Ａ），（Ｂ）に示すように、厚肉被接合材１，１の連続する両中間面２ｂ，２ｂと、対向する一対の内側端面２ｃ，２ｃとで形成された凹部４内に、この凹部４と同じ断面を有するアルミニウム製の接続板５を装入し、接続板５と各厚肉被接合材１，１の内側端面２ｃ，２ｃとの間に突合せ部６，６を形成する。そして、図２（Ｃ），（Ｄ）に示すように、突合せ部６，６に沿って、前記同様にツール１０を用いて摩擦攪拌接合を順次施す。その結果、図２（Ｅ）に示すように、突合せ部６，６に沿って、接続板５と各厚肉被接合材１，１とを接合する平行な一対の接合線Ｗ２，Ｗ２が形成される。
【００２０】
次に、図３及び図４（Ａ），（Ｂ）に示すように、摩擦攪拌用のツール２０を接続板５の上方から挿入して、凹部４の底面（中間面２ｂ，２ｂ）と接続板５の底面との境界面７を摩擦攪拌して一体化しながら、ツール２０を接続板５に沿って移動させる。図５に示すように、摩擦攪拌用のツール２０は工具鋼からなり、回転円柱体２１と、その水平な底面である表面押え部２２の中心から同軸にて垂下する攪拌ピン２３とを備えている。表面押え部２２には、その周縁から攪拌ピン２３の基端部に向かって、底面視で略二周の渦巻状に突出する凸条２４が形成されている。この凸条２４は、図５（Ｂ）中の矢印で示す方向にツール２０が回転したときに、塑性化したメタルを攪拌ピン２３の基端部に向かって強制的に集めるような向きで形成されている。また、攪拌ピン２３の周面には、ネジ状の小さな摩擦攪拌翼２５が形成されている。この摩擦攪拌翼２５は、図５（Ｂ）中の矢印で示す方向にツール２０が回転したときに、塑性化したメタルを下方から上方に向かって（攪拌ピン２３の先端から表面押え部２２に向かって）強制的に集めるような向きで形成されている。
【００２１】
そして、回転円柱体２１と攪拌ピン２３の中心軸を接続板５の表面に垂直な向きであるいはやや傾斜させて、図示しないモータによりツール２０を回転させつつ接続板５に向けて進入させる。ツール２０の回転に伴って、凹部４の底面（中間面２ｂ，２ｂ）と接続板５の底面との境界面７付近のメタルは攪拌ピン２３により加熱され可塑化されると共に、当該部分において水平及び垂直方向に流動化され、凹部４の底面付近の厚肉被接合材１，１のメタルと接続板５の底面付近のメタルとが一体化して、境界面７の微細な隙間が塞がれる。そして、接続板５の表面を表面押え部２２で押さえ込みながら、ツール２０を接続板５の表面全面に沿って順次移動させることにより、境界面７の微細な隙間を全て塞ぐことができる。
【００２２】
ここで、ツール２０を、図３及び図４（Ｂ）に示したように、接続板５の中心付近から周縁部に向かって平面視で螺旋模様の連続的な軌跡を描くように移動させれば、境界面に残存するエアーが接合部に巻き込まれることなく接合でき、さらにツール２０を引き抜いたときに不可避的にできる孔を接続板５内に残さないようにすることができる。
もちろん、ツール２０の移動軌跡はこれに限定されるものではなく、たとえば図６（Ａ）に示すように、Ｕターンを繰り返しつつ接合線Ｗ２に平行な向きで移動させるようにしてもよいし、図６（Ｂ）に示すように、Ｕターンを繰り返しつつ接合線Ｗ２に直交する向きで移動させるようにしてもよく、これら以外の移動パターンとしてもよい。連続的にでも不連続的にでもよいが、ツール２０が接続板５の表面全面を満遍なく通過するようにして、境界面７の隙間の接合線Ｗ２方向の連続性を分断することが重要である。
【００２３】
ツール２０による摩擦攪拌が完了すると、図７（Ａ）に示すように、接続板５が、ツール２０が通過した後にできる攪拌部Ｗ３となる。攪拌部Ｗ３は境界面７を含むように形成されるので、凹部４の底面と接続板５のメタルが一体化して、境界面７の微細な隙間が塞がれた接合構造を得ることができる。
なお、図７（Ｂ）に示すように、接続板５と各厚肉被接合材１，１の内側端面２ｃ，２ｃとの突合せ部６，６（接合線Ｗ２，Ｗ２）を横断するようにツール２０を移動させれば、境界面７の隙間が塞がれるだけでなく、接合線Ｗ２，Ｗ２内のトンネル状空洞欠陥が攪拌部Ｗ３で分断されるので、より気密性の高い接合構造となる。
【００２４】
＜第二実施形態＞
図８は本発明に係る接合方法の第二実施形態の各工程を表す断面図である。本実施形態は基本的に第一実施形態と同様であるが、突合せ部６，６の摩擦攪拌接合と境界面７の摩擦攪拌の順序のみにおいて異なる。
つまり、まず図８（Ａ）に示すように、それぞれの接合端に沿って外側端面２ａと中間面２ｂと内側端面２ｃとを含む段部２が形成された一対の厚肉被接合材１，１の外側端面２ａ，２ａ同士を突き合わせて突合せ部３を形成し、該突合せ部３を摩擦攪拌接合して接合線Ｗ１を形成する。
次に図８（Ｂ）に示すように、両厚肉被接合材１，１の中間面２ｂ，２ｂと内側端面２ｃ，２ｃとで形成される凹部４に該凹部４と同一断面形状の接続板５を装入した後、接続板５の上方から摩擦攪拌用のツール２０を挿入し、凹部４の底面（中間面２ｂ，２ｂ）と接続板５の底面との境界面７を摩擦攪拌して一体化させ、境界面７を含む攪拌部Ｗ３を形成する。
最後に図８（Ｃ）に示すように、接続板５と各厚肉被接合材１，１の内側端面２ｃ，２ｃとの間の突合せ部６，６を順次あるいは同時に摩擦攪拌接合する。
【００２５】
このようにして得られる接合構造も、第一実施形態と同様、凹部４の底面と接続板５のメタルが一体化して、境界面７の微細な隙間が塞がれた気密性の高いものとなっている。
なお、第一実施形態と異なり、凹部４の底面と接続板５の底面との境界面７を摩擦攪拌して一体化させる際には、接続板５が移動しないように強固に拘束しておく必要がある。
【００２６】
＜第三実施形態＞
図９は本発明に係る接合方法の第三実施形態の各工程を表す断面図である。本実施形態は基本的に第二実施形態と同様であるが、境界面７の摩擦攪拌時のツールの挿入方向のみにおいて異なる。
つまり、まず図９（Ａ）に示すように、それぞれの接合端に沿って外側端面２ａと中間面２ｂと内側端面２ｃとを含む段部２が形成された一対の厚肉被接合材１，１の外側端面２ａ，２ａ同士を突き合わせて突合せ部３を形成し、該突合せ部３を摩擦攪拌接合して接合線Ｗ１を形成する。
次に図９（Ｂ）に示すように、両厚肉被接合材１，１の中間面２ｂ，２ｂと内側端面２ｃ，２ｃとで形成される凹部４に該凹部４と同一断面形状の接続板５を装入した後、接続板５の下方（接合線Ｗ１側）から摩擦攪拌用のツール２０を挿入し、凹部４の底面（中間面２ｂ，２ｂ）と接続板５の底面との境界面７を摩擦攪拌して一体化させ、境界面７を含む攪拌部Ｗ３を形成する。
最後に図９（Ｃ）に示すように、接続板５と各厚肉被接合材１，１の内側端面２ｃ，２ｃとの間の突合せ部６，６を順次あるいは同時に摩擦攪拌接合する。
【００２７】
＜第四実施形態＞
図１０は本発明に係る接合方法の第四実施形態の各工程を表す断面図である。本実施形態は基本的に第一実施形態と同様であるが、突合せ部６，６の摩擦攪拌接合と境界面７の摩擦攪拌の順序のみにおいて異なる。
つまり、まず図１０（Ａ）に示すように、それぞれの接合端に沿って外側端面２ａと中間面２ｂと内側端面２ｃとを含む段部２が形成された一対の厚肉被接合材１，１の外側端面２ａ，２ａ同士を突き合わせて突合せ部３を形成し、該突合せ部３を摩擦攪拌接合して接合線Ｗ１を形成する。
次に図１０（Ｂ），（Ｃ）に示すように、両厚肉被接合材１，１の中間面２ｂ，２ｂと内側端面２ｃ，２ｃとで形成される凹部４に該凹部４と同一断面形状の接続板５を装入した後、接続板５の上方から摩擦攪拌用のツール２０を挿入し、凹部４の底面（中間面２ｂ，２ｂ）と接続板５の底面との境界面７を摩擦攪拌するとともに、接続板５と各厚肉被接合材１，１の内側端面２ｃ，２ｃとの間の突合せ部６，６を摩擦攪拌接合する。つまり、突合せ部６，６の摩擦攪拌接合と境界面７の摩擦攪拌とを区別せず、突合せ部６，６を包含するように摩擦攪拌を行うことにより、接続板５と各厚肉被接合材１，１との接合と、境界面７を含む攪拌部Ｗ３の形成を同時並行的に行うのである。したがって、作業工程の簡略化を図ることが可能である。
【００２８】
＜第五実施形態＞
図１１は本発明に係る接合方法の第五実施形態の各工程を表す断面図である。本実施形態は、突合せ部３の接合タイミングのみにおいて上記各実施形態と異なる。
つまり、まず図１１（Ａ）に示すように、それぞれの接合端に沿って外側端面２ａと中間面２ｂと内側端面２ｃとを含む段部が形成された一対の厚肉被接合材１，１の外側端面２ａ，２ａ同士を突き合わせて突合せ部３を形成するとともに、両厚肉被接合材１，１の中間面２ｂ，２ｂと内側端面２ｃ，２ｃとで形成される凹部に該凹部と同一の断面形状の接続板５を装入する。
次に図１１（Ｂ）に示すように、下方から摩擦攪拌接合用のツールを挿入し、突合せ部３を摩擦攪拌接合して接合線Ｗ１を形成する。
続いて図１１（Ｃ）に示すように、上方から摩擦攪拌接合用のツールを挿入し、突合せ部６，６を摩擦攪拌接合して接合線Ｗ２，Ｗ２を形成する。
最後に図１１（Ｄ）に示すように、上方から摩擦攪拌用のツールを挿入し、凹部の底面（中間面２ｂ，２ｂ）と接続板５の底面との境界面７を摩擦攪拌して一体化させ、境界面７を含む攪拌部Ｗ３を形成する。摩擦攪拌用のツールは下から挿入することも可能である。
【００２９】
なお、図１１（Ａ）の後の図１１（Ｂ）〜（Ｄ）の順序は任意に変更可能であり、最終的に接合線Ｗ１，Ｗ２と攪拌部Ｗ３を形成できればよい。
【００３０】
＜第六実施形態＞
図１２は本発明に係る接合方法の第六実施形態の各工程を表す断面図である。本実施形態では、各厚肉被接合材１，１の接合端に沿って上面側に二段の段部２，２’が形成されている。
図１２（Ａ）に示すように、厚肉被接合材１，１は厚さ１０〜１５ｍｍで、それぞれの接合端に沿って二段の段部２，２’が形成されている。段部２は外側端面２ａと第一中間面２ｂと第一内側端面２ｃとで形成され、段部２’は第一内側端面２ｃと第二中間面２ｂ’と第二内側端面２ｃ’とで形成されている。そして、このような一対の厚肉被接合材１，１の外側端面２ａ，２ａ同士を突き合わせて突合せ部３を形成する。すると、第一中間面２ｂ，２ｂと第一内側端面２ｃ，２ｃとで幅狭の凹部４が形成され、第二中間面２ｂ’，２ｂ’と第二内側端面２ｃ’，２ｃ’とで幅広の凹部４’が形成される。
続いて図１２（Ｂ）に示すように、凹部４に該凹部４と同一断面形状の接続板５を装入した上で、上記各実施形態と同様に、突合せ部３，６，６の摩擦攪拌接合による接合線Ｗ１，Ｗ２を形成するとともに、境界面７の摩擦攪拌により攪拌部Ｗ３を形成する。
最後に図１２（Ｃ）に示すように、凹部４’に該凹部４’と同一断面形状の接続板５’を装入した上で、上記各実施形態と同様に、接続板５’と各厚肉被接合材１，１の第二内側端面２ｃ’，２ｃ’との間の突合せ部６’，６’を摩擦攪拌接合するとともに、接続板５’の底面と凹部４’の底面（第二中間面２ｂ’，２ｂ’及び接続板５の上面）との境界面７’を摩擦攪拌して攪拌部Ｗ３を形成する。
【００３１】
＜第七実施形態＞
図１３は本発明に係る接合方法の第七実施形態の各工程を表す断面図である。本実施形態では、各厚肉被接合材１，１の接合端に沿って形成された段部２が、底広凹溝２ｄを有する。つまり図１３（Ａ）に示すように、段部２は、外側端面２ａと中間面２ｂと底広凹溝２ｄと内側端面２ｃとで形成されている。
そしてまず同図に示すように、これら一対の厚肉被接合材１，１の外側端面２ａ，２ａ同士を突き合わせて突合せ部３を形成し、該突合せ部３を摩擦攪拌接合して接合線Ｗ１を形成する。
次に図１３（Ｂ）に示すように、両厚肉被接合材１，１の中間面２ｂ，２ｂと内側端面２ｃ，２ｃと底広凹溝２ｄ，２ｄとで形成される凹部４に該凹部４と同一断面形状の接続板５をスライド装入した後、接続板５と各厚肉被接合材１，１の内側端面２ｃ，２ｃとの間の突合せ部６，６を摩擦攪拌接合する。接続板５は、底広凹溝２ｄ，２ｄに嵌合する底広凸条５ｄ，５ｄを有している。
最後に図１３（Ｃ）に示すように、接続板５の上方から摩擦攪拌用のツールを挿入し、凹部４の底面（中間面２ｂ，２ｂ及び底広凹溝２ｄ，２ｄの底面）と接続板５の底面との境界面７を摩擦攪拌して攪拌部Ｗ３を形成する。
【００３２】
このように、本発明における境界面７は、一水平面に限定されるわけではなく、二段以上の水平面を有するものであってもよいなど、その態様は任意である。また、図１３（Ａ）〜（Ｃ）の順序は適宜変更可能である。
【００３３】
＜第八実施形態＞
図１４は本発明に係る接合方法の第八実施形態の各工程を表す断面図である。本実施形態では、接合すべき一対の厚肉被接合材のうちの一方の厚肉被接合材１の厚さが他方の厚肉被接合材１’の厚さよりも大きくなっている。つまり図１４（Ａ）に示すように、一方の厚肉被接合材１の接合端には、外側端面２ａと中間面２ｂと内側端面２ｃとからなる段部２が形成されており、他方の厚肉被接合材１’の接合端には、外側端面２ａと中間面２ｂと内側端面２ｃ’とからなる段部２’が形成されているが、内側端面２ｃの高さは内側端面２ｃ’の高さよりも大きい。
そしてまず同図に示すように、これら一対の厚肉被接合材１，１’の外側端面２ａ，２ａ同士を突き合わせて突合せ部３を形成し、該突合せ部３を摩擦攪拌接合して接合線Ｗ１を形成する。
次に図１４（Ｂ）に示すように、両厚肉被接合材１，１’の中間面２ｂ，２ｂと内側端面２ｃ，２ｃ’とで形成される凹部４に該凹部４と相似断面形状の接続板５を装入した後、接続板５と各厚肉被接合材１，１’の内側端面２ｃ，２ｃ’との間の突合せ部６，６’を摩擦攪拌接合する。接続板５の上面は、凹部４に装入されたときにそれぞれ厚肉被接合材１，１’の上面と同一高さとなるような第一水平面５ａ、第二水平面５ｂと、第一水平面５ａと第二水平面５ｂとをつなぐ斜面５ｃとで形成されている。
最後に図１４（Ｃ）に示すように、接続板５の上方から摩擦攪拌用のツールを挿入し、凹部４の底面（中間面２ｂ，２ｂ）と接続板５の底面との境界面７を摩擦攪拌して攪拌部Ｗ３を形成する。
【００３４】
このように本発明は、一対の厚肉被接合材の厚さが異なる場合にも対応可能である。また、図１４（Ａ）〜（Ｃ）の順序は適宜変更可能である。
【００３５】
＜第九実施形態＞
図１５は本発明に係る接合方法の第九実施形態の各工程を表す断面図である。本実施形態では、各厚肉被接合材１，１の接合端に沿って上下両側にそれぞれ段部２，２’が形成されている。
図１５（Ａ）に示すように、厚肉被接合材１，１は厚さ１０〜１５ｍｍで、それぞれ接合端に沿って上段の段部２と下段の段部２’が形成されている。上段の段部２は外側端面２ａと第一中間面２ｂと第一内側端面２ｃとで形成され、下段の段部２’は外側端面２ａと第二中間面２ｂ’と第二内側端面２ｃ’とで形成されている。そして、このような一対の厚肉被接合材１，１の外側端面２ａ，２ａ同士を突き合わせて突合せ部３を形成し、該突合せ部３を摩擦攪拌接合して接合線Ｗ１を形成する。
次に図１５（Ｂ）に示すように、両厚肉被接合材１，１の第一中間面２ｂ，２ｂと第一内側端面２ｃ，２ｃとで形成される凹部４に該凹部４と同一断面形状の接続板５を装入した後、接続板５と各厚肉被接合材１，１の第一内側端面２ｃ，２ｃとの間の突合せ部６，６を摩擦攪拌接合して接合線Ｗ２，Ｗ２を形成する。また、両厚肉被接合材１，１の第二中間面２ｂ’，２ｂ’と第二内側端面２ｃ’，２ｃ’とで形成される凹部４’に該凹部４’と同一断面形状の接続板５’を装入した後、接続板５’と各厚肉被接合材１，１の第二内側端面２ｃ’，２ｃ’との間の突合せ部６’，６’を摩擦攪拌接合して接合線Ｗ２，Ｗ２を形成する。
最後に図１５（Ｃ）に示すように、接続板５の底面と凹部４の底面（第一中間面２ｂ，２ｂ）との境界面７を摩擦攪拌して攪拌部Ｗ３を形成するとともに、接続板５’の底面（同図では上面）と凹部４の底面（第二中間面２ｂ’，２ｂ’）との境界面７’を摩擦攪拌して攪拌部Ｗ３を形成する。
【００３６】
このように本発明は、各厚肉被接合材の接合端に沿って上下両側に段部が形成されている場合にも対応可能である。また、図１５（Ｂ），（Ｃ）の順序は適宜変更可能である。
【００３７】
＜第十実施形態＞
図１６は本発明に係る接合方法の第十実施形態の各工程を表す断面図である。
図１６（Ａ）に示すように、厚肉被接合材１，１は厚さ１０〜１５ｍｍで、接合端に沿って段部２が形成されている。段部２は高さの大きな（５〜１０ｍｍの）外側端面２ａと中間面２ｂと高さの小さな（５ｍｍ以下の）内側端面２ｃとで形成されている。そして、このような一対の厚肉被接合材１，１の外側端面２ａ，２ａ同士を突き合わせて突合せ部３を形成し、該突合せ部３に上下両方から摩擦攪拌接合用のツールを装入して摩擦攪拌接合を行い、接合線Ｗ１，Ｗ１を形成する。
次に図１６（Ｂ）に示すように、両厚肉被接合材１，１の中間面２ｂ，２ｂと内側端面２ｃ，２ｃとで形成される凹部４に該凹部４と同一断面形状の接続板５を装入した後、接続板５と各厚肉被接合材１，１の内側端面２ｃ，２ｃとの間の突合せ部６，６を摩擦攪拌接合して接合線Ｗ２，Ｗ２を形成する。
最後に図１６（Ｃ）に示すように、接続板５の底面と凹部４の底面（中間面２ｂ，２ｂ）との境界面７を摩擦攪拌して攪拌部Ｗ３を形成する。
【００３８】
このように本発明は、各厚肉被接合材の接合端に沿って形成された段部の外側端面の高さが大きい場合にも対応可能である。また、図１６（Ｂ），（Ｃ）の順序は適宜変更可能である。
【００３９】
＜第十一実施形態＞
図１７は本発明に係る接合方法の第十一実施形態の各工程を表す断面図である。本実施形態では、各厚肉被接合材１，１の接合端に沿って上下両面側にそれぞれ段部２，２’が形成されている。
図１７（Ａ）に示すように、厚肉被接合材１，１は厚さ１５〜２０ｍｍで、それぞれ接合端に沿って上段の段部２と下段の段部２’が形成されている。上段の段部２は外側端面２ａと第一中間面２ｂと第一内側端面２ｃとで形成され、下段の段部２’は外側端面２ａと第二中間面２ｂ’と第二内側端面２ｃ’とで形成されている。外側端面２ａの高さは５〜１０ｍｍである。そして、このような一対の厚肉被接合材１，１の外側端面２ａ，２ａ同士を突き合わせて突合せ部３を形成し、該突合せ部３に上下両方から摩擦攪拌接合用のツールを装入して摩擦攪拌接合を行い、接合線Ｗ１，Ｗ１を形成する。
次に図１７（Ｂ）に示すように、両厚肉被接合材１，１の第一中間面２ｂ，２ｂと第一内側端面２ｃ，２ｃとで形成される凹部４に該凹部４と同一断面形状の接続板５を装入した後、接続板５と各厚肉被接合材１，１の第一内側端面２ｃ，２ｃとの間の突合せ部６，６を摩擦攪拌接合して接合線Ｗ２，Ｗ２を形成する。また、両厚肉被接合材１，１の第二中間面２ｂ’，２ｂ’と第二内側端面２ｃ’，２ｃ’とで形成される凹部４’に該凹部４’と同一断面形状の接続板５’を装入した後、接続板５’と各厚肉被接合材１，１の第二内側端面２ｃ’，２ｃ’との間の突合せ部６’，６’を摩擦攪拌接合して接合線Ｗ２，Ｗ２を形成する。
最後に図１７（Ｃ）に示すように、接続板５の底面と凹部４の底面（第一中間面２ｂ，２ｂ）との境界面７を摩擦攪拌して攪拌部Ｗ３を形成するとともに、接続板５’の底面（同図では上面）と凹部４の底面（第二中間面２ｂ’，２ｂ’）との境界面７’を摩擦攪拌して攪拌部Ｗ３を形成する。
【００４０】
このように本発明は、各厚肉被接合材の接合端に沿って上下両側に段部が形成され、外側端面の高さが大きい場合にも対応可能である。また、図１７（Ｂ），（Ｃ）の順序は適宜変更可能である。
【００４１】
＜第十二実施形態＞
図１８は本発明に係る接合方法の第十二実施形態の各工程を表す断面図である。本実施形態は基本的に第一乃至第五の実施形態と同じであるが、各厚肉被接合材が曲面板材である点のみにおいて異なる。
つまり、図１８（Ａ）に示すように、それぞれの接合端に沿って外側端面２ａと中間面２ｂと内側端面２ｃとを含む段部２が形成された一対の厚肉被接合材１，１の外側端面２ａ，２ａ同士を突き合わせて突合せ部３を形成し、該突合せ部３を摩擦攪拌接合して接合線Ｗ１を形成する。中間面２ｂは曲面となっている。
次に図１８（Ｂ）に示すように、両厚肉被接合材１，１の中間面２ｂ，２ｂと内側端面２ｃ，２ｃとで形成される凹部４に該凹部４と同一断面形状の接続板５を装入した後、接続板５と各厚肉被接合材１，１の内側端面２ｃ，２ｃとの間の突合せ部６，６を摩擦攪拌接合して接合線Ｗ２，Ｗ２を形成する。
最後に図１８（Ｃ）に示すように、凹部４の底面（中間面２ｂ，２ｂ）と接続板５の底面との境界面７を摩擦攪拌して一体化させ、境界面７を含む攪拌部Ｗ３を形成する。
【００４２】
このように本発明は、各厚肉被接合材が曲面板状である場合にも対応可能である。また、図１８（Ａ）〜（Ｃ）の順序は適宜変更可能である。
【００４３】
＜ツールについて＞
以上の各実施形態で用いた摩擦攪拌用のツール２０は、適宜の変更が可能である。たとえば図１９に示した摩擦攪拌用のツール２０’は、回転円柱体２１の底面である表面押え部２２の中心からずれた位置から（偏心して）円柱形の攪拌ピン２３が垂下している。このように攪拌ピン２３が回転円柱体２１に対して偏心していると、回転円柱体２１をその軸まわりに回転させたときに、攪拌ピン２３が自転するとともに回転円柱体２１の軸まわりに公転するので、境界面７の攪拌作用が増大する。攪拌ピン２３の周面には、ネジ状の小さな摩擦攪拌翼２５が形成されているので、この摩擦攪拌翼２５を利用して攪拌ピン２３を回転円柱体２２に固定することができ、攪拌ピンの突出長さも容易に調節可能である。
【００４４】
さらにまた、図２０（Ａ）〜（Ｅ）に示したツールを用いることも可能である。図２０（Ａ）のツール２０Ａは、回転円柱体２１の底面である表面押え部２２の中心からずれた位置から（偏心して）多角形柱体状の攪拌ピン２３が垂下し、表面押え部２２の周縁から攪拌ピン２３の基端部に向かって渦巻状に突出する凸条２４が形成されたものである。図２０（Ｂ）〜（Ｅ）のツール２０Ｂ〜２０Ｅはいずれも、回転円柱体２１の底面である表面押え部２２の中心からずれた位置から（偏心して）略円柱形の攪拌ピン２３が垂下しており、さらに、ツール２０Ｂは攪拌ピン２３の底面に十字形の凸条２６が形成されたもの、ツール２０Ｃは攪拌ピン２３の底面に多数の細かい直方体形状の突起２７，２７，…が格子状に形成されたもの、ツール２０Ｄは攪拌ピン２３の底面に同心円状にリング状の突起２８，２８，…が形成されたもの、ツール２０Ｅは攪拌ピン２３の周面の底面付近に複数の凹溝２９，２９，…が形成されたものである。これらのツールはいずれも境界面７の攪拌作用を増大させたものである。
【００４５】
なお、上記各実施形態では、摩擦攪拌接合用のツール１０と摩擦攪拌用のツール２０を別々のものとしたが、もちろん同一のツールで摩擦攪拌接合と摩擦攪拌の双方を行うようにしてもよい。
【００４６】
【発明の効果】
以上のように、本発明によれば、接続板の底面と凹部の底面との間の隙間や、接続板と各厚肉被接合材の内側端面との突合せ部を摩擦攪拌接合してなる接合線の内部にトンネル状空洞欠陥を残さずに、気密性の高い厚肉被接合材の接合構造を得ることができる。
【図面の簡単な説明】
【図１】（Ａ）〜（Ｄ）はそれぞれ本発明に係る接合方法の第一実施形態の各工程を表す断面図であり、（ｃ）は（Ｃ）のｃ−ｃ断面図、（ｄ）は（Ｄ）のｄ−ｄ断面図である。
【図２】（Ａ）〜（Ｅ）はそれぞれ本発明に係る接合方法の第一実施形態の各工程を表す断面図である。
【図３】本発明に係る接合方法の第一実施形態の一工程を表す斜視図である。
【図４】（Ａ）は図３のａ−ａ断面図であり、（Ｂ）は図３の平面図である。
【図５】（Ａ）は摩擦攪拌用ツールの側面図、（Ｂ）は（Ａ）の底面図、（Ｃ）は（Ｂ）のＣ−Ｃ断面図である。
【図６】（Ａ），（Ｂ）はそれぞれ、摩擦攪拌ツールの移動軌跡の別の例を表す平面図である。
【図７】（Ａ），（Ｂ）はそれぞれ、摩擦攪拌ツールの移動完了後の状態を表す断面図である。
【図８】（Ａ）〜（Ｃ）はそれぞれ本発明に係る接合方法の第二実施形態の各工程を表す断面図である。
【図９】（Ａ）〜（Ｃ）はそれぞれ本発明に係る接合方法の第三実施形態の各工程を表す断面図である。
【図１０】（Ａ）〜（Ｃ）はそれぞれ本発明に係る接合方法の第四実施形態の各工程を表す断面図である。
【図１１】（Ａ）〜（Ｄ）はそれぞれ本発明に係る接合方法の第五実施形態の各工程を表す断面図である。
【図１２】（Ａ）〜（Ｃ）はそれぞれ本発明に係る接合方法の第六実施形態の各工程を表す断面図である。
【図１３】（Ａ）〜（Ｃ）はそれぞれ本発明に係る接合方法の第七実施形態の各工程を表す断面図である。
【図１４】（Ａ）〜（Ｃ）はそれぞれ本発明に係る接合方法の第八実施形態の各工程を表す断面図である。
【図１５】（Ａ）〜（Ｃ）はそれぞれ本発明に係る接合方法の第九実施形態の各工程を表す断面図である。
【図１６】（Ａ）〜（Ｃ）はそれぞれ本発明に係る接合方法の第十実施形態の各工程を表す断面図である。
【図１７】（Ａ）〜（Ｃ）はそれぞれ本発明に係る接合方法の第十一実施形態の各工程を表す断面図である。
【図１８】（Ａ）〜（Ｃ）はそれぞれ本発明に係る接合方法の第十二実施形態の各工程を表す断面図である。
【図１９】（Ａ）は摩擦攪拌用ツールの別の例を表す斜視図であり、（Ｂ）は同断面図である。
【図２０】（Ａ）〜（Ｅ）はそれぞれ摩擦攪拌用ツールの別の例を表す斜視図である。
【図２１】（Ａ）〜（Ｄ）は従来の接合方法の各工程を表す断面図である。
【図２２】図２０（Ｄ）の部分拡大斜視図である。
【符号の説明】
１ … 厚肉被接合材
２ … 段部
２ａ … 外側端面
２ｂ … 中間面
２ｃ … 内側端面
２ｄ … 底広凹溝
３ … 突合せ部
４ … 凹部
５ … 接続板
５ａ … 第一水平面
５ｂ … 第二水平面
５ｃ … 斜面
５ｄ … 底広凸条
６ … 突合せ部
７ … 境界面
８ … 隙間
１０ … （摩擦攪拌接合用の）ツール
１１ … 回転円柱体
１２ … 表面押え部
１３ … 攪拌ピン
２０ … （摩擦攪拌用の）ツール
２１ … 回転円柱体
２２ … 表面押え部
２３ … 攪拌ピン
２４ … 凸条
２５ … 摩擦攪拌翼
２６ … 凸条
２７ … 突起
２８ … 突起
２９ … 凹溝
Ｗ１，Ｗ２ … 接合線
Ｗ３ … 攪拌部[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a method and a structure for joining thick materials to be joined without a gap.
[0002]
[Prior art]
Patent Document 1 discloses a method of friction stir welding thick materials to be joined. As the procedure, first, as shown in FIG. 21 (A), a stepped portion 2 comprising an outer end surface 2a, an intermediate surface 2b, and an inner end surface 2c is provided at each joining end of a pair of thick workpieces 1 and 1. Form it. Then, as shown in FIG. 21 (B), the outer end surfaces 2a, 2a of the pair of thick workpieces 1, 1 are butted together to form a butted portion 3, and the friction stir welding is performed along the butted portion 3 By inserting the tool 10 and performing friction stir welding, both thick workpieces 1 and 1 are joined to form a joining line W1. Next, as shown in FIG. 21 (C), the concave portion 4 formed by the intermediate surfaces 2b, 2b and the inner end surfaces 2c, 2c of both thick-walled members 1, 1 is the same as or similar to the concave portion 4. A connecting plate 5 having a cross-sectional shape is inserted. Finally, as shown in FIG. 21 (D), the friction stir welding tool 10 is inserted along the butted portions 6 and 6 between the connecting plate 5 and the inner end surfaces 2c and 2c of the respective thick-walled members 1 and 1. Then, by performing friction stir welding, the joining lines W2 and W2 are formed. Thus, by performing friction stir welding in two stages in the thickness direction of the materials to be joined, thick materials to be joined that cannot be handled by existing joining tools can be joined together.
[0003]
[Patent Document 1]
Japanese Patent No. 3307330 ([0013]-[0018], FIG. 1-2)
[0004]
[Problems to be solved by the invention]
However, in the joining structure joined by the above-described conventional method, as shown in FIG. 22, the bottom surface of the connection plate 5 and the bottom surface of the recess 4 (intermediate surfaces 2b and 2b of each thick material to be joined 1, 1) May remain unbonded and the gap 8 may remain. In addition, a tunnel-like cavity that is continuous in the direction of travel of the tool is formed in a joining line W2 formed by friction stir welding of the butted portion 6 between the connecting plate 5 and the inner end faces 2c, 2c of the thick-walled workpieces 1, 1. The defect 9 may remain. The gap 8 and the tunnel-like cavity defect 9 reduce the hermeticity of the portion. Therefore, when this junction structure is used in, for example, a vacuum processing container of a semiconductor manufacturing apparatus, leakage is likely to occur, There is a problem that it cannot be kept for a long time in an ultra-high vacuum state.
[0005]
The present invention has been made in view of such circumstances, and a thick-walled material joining method (hereinafter simply referred to as a “joining method”) and a thick-walled material to be joined together without gaps between the thick-walled materials. It proposes a joining structure of materials (hereinafter simply referred to as “joining structure”).
[0006]
That is, in the invention according to claim 1, the outer end surfaces of a pair of thick-joined materials in which stepped portions including an outer end surface, an intermediate surface, and an inner end surface are formed along the respective joining ends. A connecting plate having the same or similar cross-sectional shape as the concave portion is inserted into the concave portion formed by the first step of friction stir welding the butt portion and the intermediate surface and the inner end surface of the both thick workpieces. The second step;
And a third step of friction-stirring the boundary surface between the connection plate and the bottom surface of the recess, after the friction stir welding of the abutting portions of the connection plate and the inner end face of each thick-walled material to be joined, respectively. In the third step, the friction stir at the boundary surface between the connection plate and the bottom surface of the recess in the third step, the inner end surface of the connection plate and each thick-walled material It is characterized by being applied across the abutting part.
In the invention according to claim 2, the outer end faces of the pair of thick-walled members formed with stepped portions including the outer end face, the intermediate face, and the inner end face are joined to each other along the joining ends. A first step of inserting a connecting plate having a cross-sectional shape identical or similar to the concave portion into the concave portion formed by the intermediate surface and the inner end surface of the both thick-walled materials, and the pair of thick-walled materials After performing friction stir welding on the butting portion formed by butting the outer end surfaces of the material and the butting portion between the connection plate and the inner end surface of each thick-joined material, the connection plate and the recess A second step of friction-stirring the boundary surface with the bottom surface, and a friction method of the boundary surface between the connection plate and the bottom surface of the recess in the second step. Stirring is performed between the connection plate and the inner end face of each of the thick workpieces. And characterized by applying across the mating portion.
Furthermore, the invention according to claim 3 includes a pair of thick members to be joined in which stepped portions including an outer end surface, an intermediate surface, and an inner end surface are formed along each joint end, and the outer end surfaces are abutted with each other. A connecting plate having a cross-sectional shape that is the same as or similar to the concave portion, and is inserted into a concave portion formed by an intermediate surface and an inner end surface of the both thick-walled materials. After the friction stir welding of the abutting portion formed by abutting the outer surfaces of each other, and the abutting portion between the connection plate and the inner end surface of each thick-walled material, the connection plate and the bottom surface of the recess The boundary surface of the thick-walled material to be frictionally agitated is a structure in which frictional agitation at the boundary surface between the connection plate and the bottom surface of the recess is performed on the inner side of the connection plate and each thick-walled material. It is characterized by being applied across the abutting portion with the end face.
[0007]
According to such a joining method or joining structure, since the boundary surface between the connection plate and the bottom surface of the recess, which has been left unjoined in the conventional joining method or joining structure, is integrated by friction stirring, A highly airtight joint with no gap can be formed.
Further, according to the joining method or the joining structure, before the friction stirring on the boundary surface between the connection plate and the bottom surface of the concave portion, the butt portion formed by butting the outer end faces of the pair of thick-walled materials to be joined is connected. Since the friction stir welding for the butted portion between the plate and the inner end face of each thick-walled workpiece is completed, the connection plate can be easily positioned and fixed during friction stirring.
Further, according to the joining method or structure, since the friction stir is performed across the abutting portion between the connection plate and the inner end face of each thick-walled material, a tunnel-like cavity defect is generated when the friction stir welding is performed. Even if this occurs, the tunnel-like cavity defect can be divided to further improve the airtightness.
[0014]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings. In the description, the same reference numerals are used for the same elements, and duplicate descriptions are omitted. In addition, it is assumed that a thick aluminum plate is used as the thick member to be joined and the joining ability of the friction stir welding apparatus is 5 mm.
[0015]
<First embodiment>
1-4 is sectional drawing showing each process of 1st embodiment of the joining method which concerns on this invention.
First, as shown in FIG. 1 (A), a pair of thick materials to be joined 1, 1 are brought into surface contact with their respective outer end faces 2a, 2a to form a butt portion 3 and are not shown. Restrain with a jig. The thickness of each thick member 1 is 5 to 10 mm, and the step portion 2 is formed along each joining end. The step portion 2 is formed to include an outer end surface 2a, an intermediate surface 2b, and an inner end surface 2c. Then, when the outer end surfaces 2a, 2a of the pair of thick members 1 and 1 are abutted with each other, the concave portions 4 are formed by the continuous intermediate surfaces 2b, 2b and the pair of opposed inner end surfaces 2c, 2c. Is done. Note that the thick-walled material 1 is made by cutting an aluminum rolled plate (AA5052 alloy, AA6061 alloy) or aluminum in which the step portion 2 is integrally formed in advance (JIS; A6063-T5 or T6). Extrusion shapes of
[0016]
Next, as shown in FIG. 1B, a tool 10 for friction stir welding is set on the butt 3. The tool 10 is made of tool steel, and includes a rotating cylindrical body 11 and an agitating pin 13 that hangs coaxially from the center of the surface pressing portion 12 that is the bottom surface of the rotating cylindrical body and is gently curved and recessed. The stirring pin 13 is slightly shorter than the height of the outer end surface 2a and the inner end surface 2c of the thick-walled workpiece 1, and a small screw-shaped friction stirring blade (not shown) is formed on the peripheral surface. 1 (C) and 1 (c), the central axes of the rotating cylindrical body 11 and the stirring pin 13 are slightly inclined along the abutting portions 3 of the respective thick-walled members 1 and 1. The tool 10 is rotated toward the butting portion 3 while being rotated by a motor (not shown). The rotation speed of the tool 10 is appropriately selected within the range of 300 to 5000 rpm. In addition, the thick materials 1 and 1 are constrained so as not to move in the longitudinal direction and the width direction in advance.
[0017]
Next, as shown in the drawing, the tool 10 is pressed in the vertical direction against each thick member 1 and the stirring pin 13 is pushed in until the entire surface pressing portion 12 reaches the surfaces of the intermediate surfaces 2b and 2b. In this state, the tool 10 is moved in the direction opposite to the inclined direction (leftward in FIG. 1C). This feed speed is appropriately selected within the range of 0.02 to 2 m / min. As the tool 10 rotates and moves, the metal in the vicinity of the butt 3 is heated and plasticized by the stirring pin 13, and the horizontal and vertical directions between the left and right thick workpieces 1 and 1 of the butt 3 are also shown. Fluidized.
[0018]
Further, the fluidized metal is given a constant pressure to the vertical flow by the surface pressing portion 12 of the tool 10 and is prevented from scattering from the vicinity of the surface of the butting portion 3 to the outside. As a result, as shown in FIGS. 1D and 1D, after the tool 10 passes, the fluidized metal is solidified from the fluidized state to become a joint line W1 having a substantially semi-elliptical cross section. . The surface of the bonding line W1 is slightly concaved by the surface pressing portion 12 by the width corresponding to the diameter, but becomes a bonding line W1 that is continuous along the butt portion 3 for a required length and has a flat surface. .
[0019]
Next, as shown in FIGS. 2 (A) and 2 (B), a recess formed by both continuous intermediate surfaces 2b and 2b of the thick material to be joined 1 and 1 and a pair of opposed inner end surfaces 2c and 2c. 4, a connecting plate 5 made of aluminum having the same cross section as the concave portion 4 is inserted, and a butt portion 6, between the connecting plate 5 and the inner end faces 2c, 2c of the respective thick-walled members 1, 1 is inserted. 6 is formed. Then, as shown in FIGS. 2C and 2D, friction stir welding is sequentially performed along the butt portions 6 and 6 using the tool 10 in the same manner as described above. As a result, as shown in FIG. 2 (E), a pair of parallel joining lines W2 and W2 for joining the connecting plate 5 and the respective thick-walled joined materials 1 and 1 are formed along the butted portions 6 and 6. Is done.
[0020]
Next, as shown in FIGS. 3 and 4 (A) and 4 (B), a friction stirring tool 20 is inserted from above the connection plate 5 and connected to the bottom surface (intermediate surfaces 2b, 2b) of the recess 4. The tool 20 is moved along the connecting plate 5 while integrating the boundary surface 7 with the bottom surface of the plate 5 by friction stirring. As shown in FIG. 5, the friction stirring tool 20 is made of tool steel, and includes a rotating cylindrical body 21 and a stirring pin 23 that hangs coaxially from the center of a surface pressing portion 22 that is a horizontal bottom surface thereof. Yes. The surface pressing portion 22 is formed with a ridge 24 that protrudes from its periphery toward the base end portion of the stirring pin 23 in a spiral shape of approximately two turns in a bottom view. The ridges 24 are formed in such a direction that the plasticized metal is forcibly collected toward the base end of the stirring pin 23 when the tool 20 rotates in the direction indicated by the arrow in FIG. Has been. Further, a small screw-shaped friction stirring blade 25 is formed on the peripheral surface of the stirring pin 23. When the tool 20 rotates in the direction indicated by the arrow in FIG. 5B, the friction stirring blade 25 moves the plasticized metal upward from below (from the tip of the stirring pin 23 to the surface pressing portion 22). It is formed in such a direction as to forcibly collect.
[0021]
Then, the central axis of the rotating cylindrical body 21 and the stirring pin 23 is inclined in a direction perpendicular to the surface of the connection plate 5 or slightly inclined, and the tool 20 is rotated toward the connection plate 5 by a motor (not shown). As the tool 20 rotates, the metal in the vicinity of the boundary surface 7 between the bottom surface (intermediate surface 2b, 2b) of the recess 4 and the bottom surface of the connection plate 5 is heated and plasticized by the stirring pin 23, and is horizontal in the portion. And the metal of the thick materials 1 and 1 near the bottom surface of the recess 4 and the metal near the bottom surface of the connection plate 5 are integrated to close a fine gap on the boundary surface 7. . Then, by moving the tool 20 sequentially along the entire surface of the connection plate 5 while pressing the surface of the connection plate 5 with the surface pressing portion 22, it is possible to close all the minute gaps on the boundary surface 7.
[0022]
Here, as shown in FIGS. 3 and 4B, the tool 20 can be moved so as to draw a spiral trace in a plan view from the vicinity of the center of the connecting plate 5 toward the peripheral edge. For example, the air remaining on the boundary surface can be joined without being caught in the joint portion, and further, holes that are unavoidable when the tool 20 is pulled out can be prevented from remaining in the connection plate 5.
Of course, the movement trajectory of the tool 20 is not limited to this. For example, as shown in FIG. 6A, the tool 20 may be moved in a direction parallel to the joining line W2 while repeating the U-turn. As shown in FIG. 6B, the U-turn may be repeated and moved in a direction orthogonal to the joining line W2, or a movement pattern other than these may be used. Although it may be continuous or discontinuous, it is important that the tool 20 passes through the entire surface of the connection plate 5 so as to divide the continuity of the gap of the boundary surface 7 in the direction of the joint line W2. .
[0023]
When the friction stirring by the tool 20 is completed, as shown in FIG. 7A, the connection plate 5 becomes the stirring portion W3 that is formed after the tool 20 passes. Since the stirring portion W3 is formed so as to include the boundary surface 7, the bottom surface of the concave portion 4 and the metal of the connection plate 5 are integrated, and a joining structure in which a minute gap in the boundary surface 7 is blocked can be obtained. .
In addition, as shown to FIG. 7 (B), it is so that the butt | matching parts 6 and 6 (joining line W2, W2) of the connection board 5 and the inner side end surfaces 2c and 2c of each thick to-be-joined material 1 and 1 may be crossed. If the tool 20 is moved, not only the gap of the boundary surface 7 is blocked, but also the tunnel-like cavity defect in the joining lines W2, W2 is divided by the stirring part W3. Become.
[0024]
<Second embodiment>
FIG. 8 is a cross-sectional view showing each step of the second embodiment of the joining method according to the present invention. This embodiment is basically the same as the first embodiment, but differs only in the order of the friction stir welding of the butt portions 6 and 6 and the friction stirring of the boundary surface 7.
That is, first, as shown in FIG. 8 (A), a pair of thick members to be joined 1 in which stepped portions 2 including an outer end surface 2a, an intermediate surface 2b, and an inner end surface 2c are formed along the respective joining ends. The outer end surfaces 2a, 2a of the first one are butted together to form a butted portion 3, and the butted portion 3 is friction stir welded to form a joining line W1.
Next, as shown in FIG. 8 (B), a connection having the same cross-sectional shape as that of the recess 4 is made to the recess 4 formed by the intermediate surfaces 2b, 2b and the inner end surfaces 2c, 2c of the both thick workpieces 1, 1. After inserting the plate 5, a friction stirring tool 20 is inserted from above the connection plate 5, and the boundary surface 7 between the bottom surface (intermediate surface 2 b, 2 b) of the recess 4 and the bottom surface of the connection plate 5 is friction stirred. And agitation part W3 including boundary surface 7 is formed.
Finally, as shown in FIG. 8C, the abutting portions 6 and 6 between the connection plate 5 and the inner end faces 2c and 2c of the respective thick-walled members 1 and 1 are friction stir welded sequentially or simultaneously.
[0025]
As in the first embodiment, the joint structure obtained in this way is also highly airtight, in which the bottom surface of the recess 4 and the metal of the connection plate 5 are integrated, and the minute gaps on the boundary surface 7 are blocked. It has become.
Unlike the first embodiment, when the boundary surface 7 between the bottom surface of the recess 4 and the bottom surface of the connection plate 5 is integrated by friction stirring, the connection plate 5 is firmly restrained so as not to move. There is a need.
[0026]
<Third embodiment>
FIG. 9 is a cross-sectional view showing each process of the third embodiment of the joining method according to the present invention. This embodiment is basically the same as the second embodiment, but differs only in the insertion direction of the tool during friction stirring of the boundary surface 7.
That is, first, as shown in FIG. 9 (A), a pair of thick-walled members 1, each having a step portion 2 including an outer end surface 2a, an intermediate surface 2b, and an inner end surface 2c along each joining end. The outer end surfaces 2a, 2a of the first one are butted together to form a butted portion 3, and the butted portion 3 is friction stir welded to form a joining line W1.
Next, as shown in FIG. 9 (B), a connection having the same cross-sectional shape as that of the recess 4 is made to the recess 4 formed by the intermediate surfaces 2b, 2b and the inner end surfaces 2c, 2c of the both thick workpieces 1, 1. After inserting the plate 5, the friction stirring tool 20 is inserted from below the connecting plate 5 (on the joining line W <b> 1 side), and the boundary between the bottom surface (intermediate surfaces 2 b, 2 b) of the concave portion 4 and the bottom surface of the connecting plate 5. The surface 7 is integrated by frictional stirring to form a stirring portion W3 including the boundary surface 7.
Finally, as shown in FIG. 9C, the abutting portions 6 and 6 between the connecting plate 5 and the inner end surfaces 2c and 2c of the respective thick-walled members 1 and 1 are friction stir welded sequentially or simultaneously.
[0027]
<Fourth embodiment>
FIG. 10 is a cross-sectional view showing each process of the fourth embodiment of the joining method according to the present invention. This embodiment is basically the same as the first embodiment, but differs only in the order of the friction stir welding of the butt portions 6 and 6 and the friction stirring of the boundary surface 7.
That is, first, as shown in FIG. 10 (A), a pair of thick members to be joined 1, each having a step portion 2 including an outer end face 2a, an intermediate face 2b, and an inner end face 2c along each joining end. The outer end surfaces 2a, 2a of the first one are butted together to form a butted portion 3, and the butted portion 3 is friction stir welded to form a joining line W1.
Next, as shown in FIGS. 10B and 10C, the concave portion 4 formed by the intermediate surfaces 2b and 2b and the inner end surfaces 2c and 2c of the both thick materials 1 and 1 is the same as the concave portion 4. After inserting the connection plate 5 having a cross-sectional shape, a friction stirring tool 20 is inserted from above the connection plate 5, and a boundary surface 7 between the bottom surface (intermediate surfaces 2 b, 2 b) of the recess 4 and the bottom surface of the connection plate 5. And abutting portions 6 and 6 between the connecting plate 5 and the inner end faces 2c and 2c of the thick-walled workpieces 1 and 1 are friction stir welded. That is, the friction stir welding of the butt portions 6 and 6 and the friction stir welding of the boundary surface 7 are not distinguished, and the friction stirrer is performed so as to include the butt portions 6 and 6, so The joining with the materials 1 and 1 and the formation of the stirring portion W3 including the boundary surface 7 are performed simultaneously. Therefore, it is possible to simplify the work process.
[0028]
<Fifth embodiment>
FIG. 11 is a cross-sectional view showing each process of the fifth embodiment of the joining method according to the present invention. This embodiment is different from the above embodiments only in the joining timing of the butting portion 3.
That is, first, as shown in FIG. 11 (A), a pair of thick materials 1 and 1 in which step portions including the outer end surface 2a, the intermediate surface 2b, and the inner end surface 2c are formed along the respective joining ends. The outer end surfaces 2a, 2a of each other are butted together to form a butting portion 3, and the recess formed by the intermediate surfaces 2b, 2b and the inner end surfaces 2c, 2c of both thick-walled materials 1, 1 is identical to the recess. The connecting plate 5 having the cross-sectional shape is inserted.
Next, as shown in FIG. 11B, a friction stir welding tool is inserted from below, and the butted portion 3 is friction stir welded to form a joining line W1.
Subsequently, as shown in FIG. 11C, a friction stir welding tool is inserted from above, and the butted portions 6 and 6 are friction stir welded to form joint lines W2 and W2.
Finally, as shown in FIG. 11D, a friction stir tool is inserted from above, and the boundary surface 7 between the bottom surface (intermediate surfaces 2b, 2b) of the recess and the bottom surface of the connecting plate 5 is friction stir to integrate. And a stirring portion W3 including the boundary surface 7 is formed. The friction stir tool can be inserted from below.
[0029]
In addition, the order of FIG. 11 (B)-(D) after FIG. 11 (A) can be changed arbitrarily, and should just form joining lines W1, W2 and the stirring part W3 finally.
[0030]
<Sixth embodiment>
FIG. 12 is a cross-sectional view showing each process of the sixth embodiment of the joining method according to the present invention. In the present embodiment, two stepped portions 2 and 2 ′ are formed on the upper surface side along the joining ends of the thick-walled workpieces 1 and 1.
As shown in FIG. 12 (A), the thick materials 1 and 1 have a thickness of 10 to 15 mm, and two stepped portions 2 and 2 'are formed along the respective joining ends. The step portion 2 is formed by the outer end surface 2a, the first intermediate surface 2b, and the first inner end surface 2c, and the step portion 2 ′ is formed by the first inner end surface 2c, the second intermediate surface 2b ′, and the second inner end surface 2c ′. Is formed. And the abutting part 3 is formed by abutting the outer end faces 2a, 2a of such a pair of thick workpieces 1,1. Then, a narrow concave portion 4 is formed by the first intermediate surfaces 2b, 2b and the first inner end surfaces 2c, 2c, and the second intermediate surfaces 2b ′, 2b ′ and the second inner end surfaces 2c ′, 2c ′ are wide. Is formed.
Subsequently, as shown in FIG. 12 (B), after the connecting plate 5 having the same cross-sectional shape as the concave portion 4 is inserted into the concave portion 4, the friction of the butted portions 3, 6, 6 is the same as in the above embodiments. While forming the joining lines W1 and W2 by stirring joining, the stirring part W3 is formed by friction stirring of the boundary surface 7. FIG.
Finally, as shown in FIG. 12C, after inserting the connecting plate 5 ′ having the same cross-sectional shape as the recessed portion 4 ′ into the recessed portion 4 ′, the connecting plate 5 ′ and The abutting portions 6 'and 6' between the thick inner members 1 and 1 and the second inner end surfaces 2c 'and 2c' are friction stir welded, and the bottom surface of the connection plate 5 'and the bottom surface of the recess 4' (first The agitating portion W3 is formed by frictional stirring of the boundary surface 7 ′ between the two intermediate surfaces 2b ′ and 2b ′ and the upper surface of the connecting plate 5).
[0031]
<Seventh embodiment>
FIG. 13 is a cross-sectional view showing each process of the seventh embodiment of the joining method according to the present invention. In this embodiment, the step part 2 formed along the joining end of each thick material 1 and 1 has the wide bottom ditch | groove 2d. That is, as shown in FIG. 13A, the step portion 2 is formed by the outer end surface 2a, the intermediate surface 2b, the wide groove 2d, and the inner end surface 2c.
First, as shown in the figure, the outer end faces 2a, 2a of the pair of thick workpieces 1, 1 are butted together to form a butted portion 3, and the butted portion 3 is friction stir welded to join line W1. Form.
Next, as shown in FIG. 13 (B), in the concave portion 4 formed by the intermediate surfaces 2b, 2b, the inner end surfaces 2c, 2c, and the wide concave grooves 2d, 2d of the both thick materials 1 and 1, After the connecting plate 5 having the same cross-sectional shape as that of the recess 4 is slide-inserted, the abutting portions 6 and 6 between the connecting plate 5 and the inner end surfaces 2c and 2c of the thick-walled workpieces 1 and 1 are friction stir welded. . The connecting plate 5 has wide bottom ridges 5d and 5d that fit into the wide bottom grooves 2d and 2d.
Finally, as shown in FIG. 13C, a friction stir tool is inserted from above the connection plate 5 and connected to the bottom surface of the concave portion 4 (the bottom surfaces of the intermediate surfaces 2b and 2b and the wide bottom concave grooves 2d and 2d). Friction stirring is performed on the boundary surface 7 with the bottom surface of the plate 5 to form a stirring portion W3.
[0032]
As described above, the boundary surface 7 in the present invention is not limited to a single horizontal plane, and may have any aspect such as one having two or more horizontal planes. Further, the order of FIGS. 13A to 13C can be changed as appropriate.
[0033]
<Eighth embodiment>
FIG. 14 is a cross-sectional view showing each process of the eighth embodiment of the joining method according to the present invention. In this embodiment, the thickness of one thick workpiece 1 of the pair of thick workpieces to be joined is larger than the thickness of the other thick workpiece 1 '. That is, as shown in FIG. 14A, a stepped portion 2 including an outer end surface 2a, an intermediate surface 2b, and an inner end surface 2c is formed at the joining end of one thick workpiece 1 and the other end A stepped portion 2 'composed of an outer end surface 2a, an intermediate surface 2b, and an inner end surface 2c' is formed at the joining end of the thick-walled workpiece 1 '. The inner end surface 2c has a height equal to the inner end surface 2c'. Greater than the height of
First, as shown in the figure, the outer end surfaces 2a, 2a of the pair of thick workpieces 1, 1 'are butted together to form a butted portion 3, and the butted portion 3 is friction stir welded to form a joining line. W1 is formed.
Next, as shown in FIG. 14 (B), the concave portion 4 formed by the intermediate surfaces 2b, 2b and the inner end surfaces 2c, 2c 'of both thick-walled members 1, 1' has a cross-sectional shape similar to the concave portion 4. After the connecting plate 5 is inserted, the abutting portions 6 and 6 ′ between the connecting plate 5 and the inner end surfaces 2c and 2c ′ of the thick-walled members 1 and 1 ′ are friction stir welded. The first horizontal surface 5a, the second horizontal surface 5b, and the first horizontal surface 5a are such that the upper surface of the connecting plate 5 has the same height as the upper surfaces of the thick materials 1 and 1 'when inserted into the recess 4. And a slope 5c connecting the second horizontal surface 5b.
Finally, as shown in FIG. 14C, a friction stir tool is inserted from above the connection plate 5, and the boundary surface 7 between the bottom surface (intermediate surfaces 2 b, 2 b) of the recess 4 and the bottom surface of the connection plate 5 is formed. Friction stirring is performed to form the stirring portion W3.
[0034]
As described above, the present invention can be applied to a case where the thickness of the pair of thick members to be joined is different. In addition, the order of FIGS. 14A to 14C can be changed as appropriate.
[0035]
<Ninth embodiment>
FIG. 15 is a cross-sectional view showing each process of the ninth embodiment of the joining method according to the present invention. In the present embodiment, step portions 2 and 2 ′ are formed on both the upper and lower sides along the joining ends of the respective thick-walled workpieces 1 and 1.
As shown in FIG. 15 (A), the thick members 1 and 1 have a thickness of 10 to 15 mm, and an upper step portion 2 and a lower step portion 2 ′ are formed along the joining ends. The upper step 2 is formed by an outer end surface 2a, a first intermediate surface 2b, and a first inner end surface 2c, and the lower step 2 'is formed by an outer end surface 2a, a second intermediate surface 2b', and a second inner end surface 2c '. And is formed. Then, the outer end surfaces 2a, 2a of such a pair of thick members 1 and 1 are butted together to form a butted portion 3, and the butted portion 3 is friction stir welded to form a joining line W1.
Next, as shown in FIG. 15 (B), the concave portion 4 formed by the first intermediate surfaces 2b, 2b and the first inner end surfaces 2c, 2c of both thick-walled workpieces 1, 1 is identical to the concave portion 4. After inserting the connecting plate 5 having a cross-sectional shape, the abutting portions 6 and 6 between the connecting plate 5 and the first inner end surfaces 2c and 2c of the respective thick-walled workpieces 1 and 1 are friction stir welded and joined. W2 and W2 are formed. In addition, a connection having the same cross-sectional shape as that of the recess 4 ′ is formed in the recess 4 ′ formed by the second intermediate surfaces 2b ′ and 2b ′ and the second inner end surfaces 2c ′ and 2c ′. After inserting the plate 5 ′, the abutting portions 6 ′ and 6 ′ between the connecting plate 5 ′ and the second inner end surfaces 2c ′ and 2c ′ of the thick-walled members 1 and 1 are friction stir welded. Bonding lines W2 and W2 are formed.
Finally, as shown in FIG. 15 (C), the boundary surface 7 between the bottom surface of the connection plate 5 and the bottom surface of the recess 4 (first intermediate surfaces 2b, 2b) is frictionally stirred to form a stirring portion W3 and connected. The stirrer W3 is formed by frictional stirring of the boundary surface 7 'between the bottom surface of the plate 5' (upper surface in the figure) and the bottom surface of the recess 4 (second intermediate surfaces 2b ', 2b').
[0036]
Thus, this invention can respond also to the case where the step part is formed in the up-and-down both sides along the joining end of each thick material to be joined. Further, the order of FIGS. 15B and 15C can be changed as appropriate.
[0037]
<Tenth embodiment>
FIG. 16 is a cross-sectional view showing each process of the tenth embodiment of the joining method according to the present invention.
As shown in FIG. 16 (A), the thick materials 1 and 1 have a thickness of 10 to 15 mm, and a step portion 2 is formed along the joining end. The step portion 2 is formed by an outer end surface 2a having a large height (5 to 10 mm), an intermediate surface 2b, and an inner end surface 2c having a small height (5 mm or less). Then, the abutting portion 3 is formed by abutting the outer end faces 2a, 2a of such a pair of thick workpieces 1 and 1, and a tool for friction stir welding is inserted into the abutting portion 3 from above and below. Friction stir welding is performed to form the joining lines W1, W1.
Next, as shown in FIG. 16 (B), a connection having the same cross-sectional shape as that of the recess 4 is made to the recess 4 formed by the intermediate surfaces 2b, 2b and the inner end surfaces 2c, 2c of the both thick workpieces 1, 1. After the plate 5 is inserted, the abutting portions 6 and 6 between the connecting plate 5 and the inner end surfaces 2c and 2c of the thick-walled workpieces 1 and 1 are friction stir welded to form joint lines W2 and W2. .
Finally, as shown in FIG. 16C, the agitating portion W3 is formed by frictional stirring of the boundary surface 7 between the bottom surface of the connection plate 5 and the bottom surface (intermediate surfaces 2b, 2b) of the recess 4.
[0038]
As described above, the present invention can also be applied to a case where the height of the outer end face of the step portion formed along the joining end of each thick-walled workpiece is large. In addition, the order of FIGS. 16B and 16C can be changed as appropriate.
[0039]
<Eleventh embodiment>
FIG. 17 is a cross-sectional view showing each process of the eleventh embodiment of the joining method according to the present invention. In the present embodiment, step portions 2 and 2 ′ are formed on the upper and lower surfaces along the joining ends of the thick-walled materials 1 and 1, respectively.
As shown in FIG. 17 (A), the thick members 1 and 1 have a thickness of 15 to 20 mm, and an upper step 2 and a lower step 2 ′ are formed along the joining ends. The upper step 2 is formed by an outer end surface 2a, a first intermediate surface 2b, and a first inner end surface 2c, and the lower step 2 'is formed by an outer end surface 2a, a second intermediate surface 2b', and a second inner end surface 2c '. And is formed. The height of the outer end surface 2a is 5 to 10 mm. Then, the abutting portion 3 is formed by abutting the outer end faces 2a, 2a of such a pair of thick workpieces 1 and 1, and a tool for friction stir welding is inserted into the abutting portion 3 from above and below. Friction stir welding is performed to form the joining lines W1, W1.
Next, as shown in FIG. 17 (B), the concave portion 4 formed by the first intermediate surfaces 2b, 2b and the first inner end surfaces 2c, 2c of both thick-walled workpieces 1, 1 is identical to the concave portion 4. After inserting the connecting plate 5 having a cross-sectional shape, the abutting portions 6 and 6 between the connecting plate 5 and the first inner end surfaces 2c and 2c of the respective thick-walled workpieces 1 and 1 are friction stir welded and joined. W2 and W2 are formed. In addition, a connection having the same cross-sectional shape as that of the recess 4 ′ is formed in the recess 4 ′ formed by the second intermediate surfaces 2b ′ and 2b ′ and the second inner end surfaces 2c ′ and 2c ′. After inserting the plate 5 ′, the abutting portions 6 ′ and 6 ′ between the connecting plate 5 ′ and the second inner end surfaces 2c ′ and 2c ′ of the thick-walled members 1 and 1 are friction stir welded. Bonding lines W2 and W2 are formed.
Finally, as shown in FIG. 17 (C), the boundary surface 7 between the bottom surface of the connection plate 5 and the bottom surface of the recess 4 (first intermediate surfaces 2b, 2b) is frictionally stirred to form a stirring portion W3 and connected. The stirrer W3 is formed by frictional stirring of the boundary surface 7 'between the bottom surface of the plate 5' (upper surface in the figure) and the bottom surface (second intermediate surfaces 2b ', 2b') of the recess 4.
[0040]
Thus, this invention can respond also to the case where step portions are formed on both the upper and lower sides along the joining ends of the respective thick-walled materials and the height of the outer end face is large. In addition, the order of FIGS. 17B and 17C can be changed as appropriate.
[0041]
<Twelfth embodiment>
FIG. 18 is a cross-sectional view showing each process of the twelfth embodiment of the joining method according to the present invention. The present embodiment is basically the same as the first to fifth embodiments, but differs only in that each thick-walled material is a curved plate material.
That is, as shown in FIG. 18 (A), a pair of thick members to be joined 1, 1 in which a step portion 2 including an outer end surface 2a, an intermediate surface 2b, and an inner end surface 2c is formed along each joining end. The outer end surfaces 2a, 2a are butted together to form a butted portion 3, and the butted portion 3 is friction stir welded to form a joining line W1. The intermediate surface 2b is a curved surface.
Next, as shown in FIG. 18 (B), a connection having the same cross-sectional shape as that of the recess 4 is made to the recess 4 formed by the intermediate surfaces 2b, 2b and the inner end surfaces 2c, 2c of the both thick workpieces 1, 1. After the plate 5 is inserted, the abutting portions 6 and 6 between the connecting plate 5 and the inner end surfaces 2c and 2c of the thick-walled workpieces 1 and 1 are friction stir welded to form joint lines W2 and W2. .
Finally, as shown in FIG. 18C, the boundary surface 7 between the bottom surface (intermediate surfaces 2b, 2b) of the recess 4 and the bottom surface of the connection plate 5 is integrated by frictional stirring, and the stirring unit including the boundary surface 7 is obtained. W3 is formed.
[0042]
As described above, the present invention can also be applied to the case where each thick-walled material has a curved plate shape. In addition, the order of FIGS. 18A to 18C can be changed as appropriate.
[0043]
<About tools>
The friction stirring tool 20 used in each of the above embodiments can be changed as appropriate. For example, in the friction stirring tool 20 ′ shown in FIG. 19, a cylindrical stirring pin 23 is suspended from a position shifted from the center of the surface pressing portion 22 that is the bottom surface of the rotating cylindrical body 21. When the stirring pin 23 is eccentric with respect to the rotating cylinder 21 in this way, when the rotating cylinder 21 is rotated around its axis, the stirring pin 23 rotates and revolves around the axis of the rotating cylinder 21. Therefore, the stirring action of the boundary surface 7 increases. Since the screw-shaped small friction stirring blade 25 is formed on the peripheral surface of the stirring pin 23, the stirring pin 23 can be fixed to the rotating cylindrical body 22 using the friction stirring blade 25. The projecting length of can be easily adjusted.
[0044]
Furthermore, the tools shown in FIGS. 20A to 20E can be used. In the tool 20 </ b> A of FIG. 20A, a polygonal columnar stirring pin 23 hangs down from a position shifted from the center of the surface pressing portion 22 that is the bottom surface of the rotating cylindrical body 21, and the surface pressing portion 22. A ridge 24 that protrudes in a spiral shape from the peripheral edge to the proximal end of the stirring pin 23 is formed. In each of the tools 20B to 20E shown in FIGS. 20B to 20E, the substantially cylindrical stirring pin 23 is suspended from a position shifted from the center of the surface pressing portion 22 which is the bottom surface of the rotating cylindrical body 21 (eccentrically). Further, the tool 20B has a cross-shaped protrusion 26 formed on the bottom surface of the stirring pin 23, and the tool 20C has a large number of fine rectangular parallelepiped projections 27, 27,. The tool 20D is formed with concentric ring-shaped protrusions 28, 28,... On the bottom surface of the stirring pin 23, and the tool 20E has a plurality of concave portions near the bottom surface of the peripheral surface of the stirring pin 23. Grooves 29, 29,... Are formed. All of these tools increase the stirring action of the boundary surface 7.
[0045]
In each of the above-described embodiments, the friction stir welding tool 10 and the friction stir tool 20 are separate, but of course, both the friction stir welding and the friction stirring may be performed with the same tool. .
[0046]
【The invention's effect】
As described above, according to the present invention, the gap formed between the bottom surface of the connection plate and the bottom surface of the recess, and the joint formed by friction stir welding of the butted portion between the connection plate and the inner end surface of each thick-walled workpiece. Without leaving a tunnel-like cavity defect inside the wire, it is possible to obtain a highly airtight thick-joined material joining structure.
[Brief description of the drawings]
FIGS. 1A to 1D are cross-sectional views showing respective steps of a first embodiment of a bonding method according to the present invention, and FIG. 1C is a cross-sectional view taken along line cc in FIG. ) Is a sectional view taken along the line dd of (D).
FIGS. 2A to 2E are cross-sectional views illustrating respective steps of the first embodiment of the bonding method according to the present invention.
FIG. 3 is a perspective view showing a process of the first embodiment of the joining method according to the present invention.
4A is a cross-sectional view taken along the line aa of FIG. 3, and FIG. 4B is a plan view of FIG.
5A is a side view of the friction stir tool, FIG. 5B is a bottom view of FIG. 5A, and FIG. 5C is a cross-sectional view taken along the line CC of FIG.
FIGS. 6A and 6B are plan views illustrating another example of the movement trajectory of the friction stir tool. FIG.
7A and 7B are cross-sectional views showing a state after the movement of the friction stir tool is completed.
FIGS. 8A to 8C are cross-sectional views illustrating respective steps of the second embodiment of the bonding method according to the present invention.
FIGS. 9A to 9C are cross-sectional views illustrating respective steps of the third embodiment of the bonding method according to the present invention.
FIGS. 10A to 10C are cross-sectional views illustrating respective steps of the fourth embodiment of the bonding method according to the present invention.
FIGS. 11A to 11D are cross-sectional views illustrating respective steps of a fifth embodiment of the bonding method according to the present invention.
FIGS. 12A to 12C are cross-sectional views showing respective steps of a sixth embodiment of the bonding method according to the present invention.
FIGS. 13A to 13C are cross-sectional views showing respective steps of a seventh embodiment of the joining method according to the present invention.
FIGS. 14A to 14C are cross-sectional views showing respective steps of the eighth embodiment of the joining method according to the present invention.
FIGS. 15A to 15C are cross-sectional views showing respective steps of the ninth embodiment of the joining method according to the present invention.
FIGS. 16A to 16C are cross-sectional views illustrating respective steps of a tenth embodiment of the bonding method according to the present invention.
FIGS. 17A to 17C are cross-sectional views showing respective steps of an eleventh embodiment of the bonding method according to the present invention.
FIGS. 18A to 18C are cross-sectional views illustrating respective steps of a twelfth embodiment of the bonding method according to the present invention.
19A is a perspective view showing another example of the friction stir tool, and FIG. 19B is a cross-sectional view thereof.
20A to 20E are perspective views showing another example of the friction stir tool.
FIGS. 21A to 21D are cross-sectional views showing respective steps of a conventional joining method.
22 is a partially enlarged perspective view of FIG. 20 (D). FIG.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 ... Thick to-be-joined material 2 ... Step part 2a ... Outer end surface 2b ... Intermediate | middle surface 2c ... Inner end surface 2d ... Bottom wide groove 3 ... Butt part 4 ... Concave part 5 ... Connection plate 5a ... First horizontal surface 5b ... Second horizontal surface 5c ... Slope 5d ... Broad ridge 6 ... Butt part 7 ... Boundary surface 8 ... Gap 10 ... Tool 11 (for friction stir welding) ... Rotary cylinder 12 ... Surface pressing part 13 ... Stirring pin 20 ... (For friction stirring) Tool 21 ... Rotating cylindrical body 22 ... Surface pressing part 23 ... Stirring pin 24 ... Convex streak 25 ... Friction stirrer blade 26 ... Convex streak 27 ... Protrusion 28 ... Protrusion 29 ... Concave groove W1, W2 ... Joining line W3 ... Stirring part

Claims

A first part that abuts the outer end surfaces of a pair of thick-walled members formed with stepped portions including an outer end surface, an intermediate surface, and an inner end surface along each joining end, and friction stir welds the butted portions. Process,
A second step of inserting a connection plate having the same or similar cross-sectional shape as the concave portion into the concave portion formed by the intermediate surface and the inner end surface of the both thick-walled materials;
And a third step of friction-stirring the boundary surface between the connection plate and the bottom surface of the recess after the abutting portion between the connection plate and the inner end face of each thick-walled workpiece is friction stir welded, respectively. It is a joining method of a thick-walled material consisting of
In the third step, the friction stir at the boundary surface between the connection plate and the bottom surface of the recess is performed across the abutting portion between the connection plate and the inner end surface of each thick-walled material. To join thick-walled workpieces.

While abutting the outer end surfaces of a pair of thick-walled members formed with stepped portions including an outer end surface, an intermediate surface, and an inner end surface along the respective joining ends, A first step of inserting a connection plate having the same or similar cross-sectional shape as the recess into the recess formed by the surface and the inner end surface;
After facilities and butt portion comprising butt outer end faces of the pair of thick material to be joined, and the connecting plate and the butt portion between the inner end surface of each of the thick material to be joined, each friction stir welding for A second step of friction stirring the boundary surface between the connection plate and the bottom surface of the recess, and a method for joining thick-walled workpieces comprising :
In the second step, the friction stir at the boundary surface between the connection plate and the bottom surface of the recess is performed across the abutting portion between the connection plate and the inner end surface of each thick-walled material. To join thick-walled workpieces.

A stepped portion including an outer end face, an intermediate face and an inner end face is formed along each joining end, and a pair of thick materials to be joined in which the outer end faces are abutted with each other;
A connecting plate having a cross-sectional shape that is the same as or similar to that of the concave portion, which is inserted into the concave portion formed by the intermediate surface and the inner end surface of the both thick-walled workpieces,
After the abutting portion formed by abutting the outer surfaces of the both thick-walled materials and the abutting portion between the connection plate and the inner end surface of each thick-walled material, the connection is performed after the friction stir welding is performed . The interface between the plate and the bottom surface of the recess is a joining structure of a thick-walled material in which frictional stirring is performed,
Friction stirring at the boundary surface between the connection plate and the bottom surface of the recess is performed across the abutting portion between the connection plate and the inner end surface of each thick member to be joined. Bonding structure of workpieces.