JP3775894B2 - Method for local modification of base material - Google Patents
Method for local modification of base material Download PDFInfo
- Publication number
- JP3775894B2 JP3775894B2 JP20445097A JP20445097A JP3775894B2 JP 3775894 B2 JP3775894 B2 JP 3775894B2 JP 20445097 A JP20445097 A JP 20445097A JP 20445097 A JP20445097 A JP 20445097A JP 3775894 B2 JP3775894 B2 JP 3775894B2
- Authority
- JP
- Japan
- Prior art keywords
- base material
- reforming
- probe
- locally
- recess
- 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
Links
Images
Classifications
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B23—MACHINE TOOLS; METAL-WORKING NOT OTHERWISE PROVIDED FOR
- B23K—SOLDERING OR UNSOLDERING; WELDING; CLADDING OR PLATING BY SOLDERING OR WELDING; CUTTING BY APPLYING HEAT LOCALLY, e.g. FLAME CUTTING; WORKING BY LASER BEAM
- B23K20/00—Non-electric welding by applying impact or other pressure, with or without the application of heat, e.g. cladding or plating
- B23K20/12—Non-electric welding by applying impact or other pressure, with or without the application of heat, e.g. cladding or plating the heat being generated by friction; Friction welding
- B23K20/122—Non-electric welding by applying impact or other pressure, with or without the application of heat, e.g. cladding or plating the heat being generated by friction; Friction welding using a non-consumable tool, e.g. friction stir welding
- B23K20/1275—Non-electric welding by applying impact or other pressure, with or without the application of heat, e.g. cladding or plating the heat being generated by friction; Friction welding using a non-consumable tool, e.g. friction stir welding involving metallurgical change
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B23—MACHINE TOOLS; METAL-WORKING NOT OTHERWISE PROVIDED FOR
- B23K—SOLDERING OR UNSOLDERING; WELDING; CLADDING OR PLATING BY SOLDERING OR WELDING; CUTTING BY APPLYING HEAT LOCALLY, e.g. FLAME CUTTING; WORKING BY LASER BEAM
- B23K20/00—Non-electric welding by applying impact or other pressure, with or without the application of heat, e.g. cladding or plating
- B23K20/12—Non-electric welding by applying impact or other pressure, with or without the application of heat, e.g. cladding or plating the heat being generated by friction; Friction welding
- B23K20/122—Non-electric welding by applying impact or other pressure, with or without the application of heat, e.g. cladding or plating the heat being generated by friction; Friction welding using a non-consumable tool, e.g. friction stir welding
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B23—MACHINE TOOLS; METAL-WORKING NOT OTHERWISE PROVIDED FOR
- B23K—SOLDERING OR UNSOLDERING; WELDING; CLADDING OR PLATING BY SOLDERING OR WELDING; CUTTING BY APPLYING HEAT LOCALLY, e.g. FLAME CUTTING; WORKING BY LASER BEAM
- B23K20/00—Non-electric welding by applying impact or other pressure, with or without the application of heat, e.g. cladding or plating
- B23K20/12—Non-electric welding by applying impact or other pressure, with or without the application of heat, e.g. cladding or plating the heat being generated by friction; Friction welding
- B23K20/122—Non-electric welding by applying impact or other pressure, with or without the application of heat, e.g. cladding or plating the heat being generated by friction; Friction welding using a non-consumable tool, e.g. friction stir welding
- B23K20/128—Non-electric welding by applying impact or other pressure, with or without the application of heat, e.g. cladding or plating the heat being generated by friction; Friction welding using a non-consumable tool, e.g. friction stir welding making use of additional material
Landscapes
- Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- Pressure Welding/Diffusion-Bonding (AREA)
- Other Surface Treatments For Metallic Materials (AREA)
Description
【0001】
【発明の属する技術分野】
この発明は、各種工業分野において使用される金属等よりなる母材の一部分の特性、例えば硬さ、電気伝導度、磁気特性等を、当該母材とは異なるように改質するための局部的改質方法に関する。
【0002】
【従来技術とその課題】
近年、各種工業分野における製造工程や製品自体の高機能化に伴い、例えば硬さ、電気伝導度、磁気特性等の特性が局部的に異なる材料の需要が増大すると共に、このような材料として特に耐久性及び信頼性に優れて且つ安価なものが希求されている。ところが、従来におけるこの種の材料は、一般的に母材の一部に特性の異なる異種材料を接合した形態であるため、その接合強度が不充分で耐久性に乏しかったり、溶融接合では接合部にクラックの発生や組織の変質を生じて品質低下をきたす等の問題を生じることが多い上、接合に要するコストが高く付くという難点があった。
【0003】
例えば、各種工場の自動生産システムにおいては、加工用及び組立用の各種機器の動作や移動、ワークの移動等のために多くのガイドレールが設けられるが、その耐摩耗性を向上させる手段として、ガイドレール母材の他との接触部分に母材金属とは異なる硬質金属の板材を接合させることが多い。しかるに、異種金属間では密着性に乏しいため、接合界面が剥離して浮き上がり等を生じ易く、耐久性に劣るという問題があった。また、自動車等のエンジンに使用されるピストンでは、ピストンの母材にリング状の異種金属を融着させてピストンリング部を形成する方法が多用されているが、その融着後の凝固時にピストンリング部に微小なクラックが発生し易いという問題があった。
【0004】
この発明は、上述の事情に鑑みて、母材の一部を異なる特性を持つように局部的に改質する手段として、改質部に実質的な接合界面を生じず、もって界面剥離等による耐久性の低下が防止されると共に、熱影響によるクラックの発生や変質による品質低下を回避できる上、加工を容易に且つ低コストで行える方法を提供することを目的としている。
【0005】
【課題を解決するための手段】
この発明者らは、上記目的を達成するために鋭意検討を行う過程で、近年において金属材の溶接やロウ付けに代わる新しい接合技術として普及しつつある摩擦攪拌接合法に着目し、これを母材の局部改質に応用することを考えた。
【0006】
この摩擦攪拌接合法は、例えば特表平7−505090号公報に開示されるように、被加工物よりも硬い材質のプローブ(棒状物)を回転させながら被加工物に摺接させた際に、この摺接部分で発生する摩擦熱と圧力によって被加工物素材が塑性流動化し、該プローブが被加工物中に埋入して且つこの埋入状態のまま被加工物中を移動できることを利用したものであり、例えば金属板同士の突き合わせ接合線に沿ってプローブを上記埋入状態で移動させると、進行するプローブの前方側で塑性流動した両金属板の素材が攪拌混練されながら該プローブの後方側へ漸次移行し、後方側で摩擦熱を失って急速に冷却固化するから、両金属板は素材同士が攪拌混練されて完全に一体化した状態で接合されることになる。
【0007】
しかして、この発明者らは、摩擦攪拌接合法における金属素材の塑性流動化現象を、一般的な金属材同士の接合ではなく、母材の局部的改質に利用するという独特の発想のもとに、綿密な実験研究を重ねた結果、前記接合に使用するのと同様の加工用ツールを用い、簡単な手法によって上記の局部的改質を容易に行えることを見出し、この発明をなすに至った。
【0008】
すなわち、この発明の請求項1に係る母材の局部的改質方法は、図面の参照符号を付して示せば、母材(1)の改質を要する領域(1a)に改質用材料(2)を配置し、この改質用材料(2)の配置部に、加工用ツール(3)の回転子(31)に突設されたプローブ(32)を回転しつつ埋入させると共に、この埋入状態で当該ツール(3)を前記改質用材料(2)の配置部に沿って移動させることにより、埋入した前記プローブ(32)の回転に伴う摩擦攪拌によって改質用材料(2)と母材(1)の素材とを一体化することを特徴としている。
【0009】
上記構成では、プローブ(32)が改質用材料(2)の配置部に埋入すると、母材(1)の素材が摩擦攪拌によって塑性流動するが、このとき流動する素材中に改質用材料(2)が混ざり込んで一緒に流動することになる。しかして、この流動する材料は回転する該プローブ(32)の移動に伴い、攪拌混練されながら該プローブ(32)の後方側へ漸次移行し、後方側で摩擦熱を失って急速に冷却固化する。この固化部分は、母材(1)の素材と改質用材料(2)とが混練されて完全に一体化しており、改質用材料(2)に基づく所要の特性を具備する改質領域となる。
【0010】
従って、母材(1)と改質用材料(2)との接合界面は存在せず、また母材 (1)の素材に対する改質用材料(2)の混ざり込みは前記固化部分の周辺ほど少なくなる、なだらかな分布を示すため、改質部分とその周囲との間でも明確な界面が形成されない。しかして、この摩擦攪拌では、溶融法とは異なって材料の塑性流動化が融点よりもかなり低い温度で生じ、固化部分は母材(1)の素材と改質用材料(2)とが殆ど固相で混合した状態になり、溶融法のような凝固組織ではないからクラックの発生や熱変質を生起しにくく、両者が金属であっても金属間化合物の生成が抑制される。
【0011】
請求項2の発明では、上記請求項1の母材の局部的改質方法において、母材 (1)の改質を要する領域に凹所(11)を形成し、この凹所(11)内に改質用材料(2)を配置する構成としているから、プローブ(32)を埋入状態で移動させる際に改質用材料(2)が配置位置から逃げにくく、もって母材(1)の素材と改質用材料(2)とが摩擦攪拌によって効率よく混練されることになる。
【0012】
請求項3の発明では、上記請求項2の母材の局部的改質方法において、改質用材料(2)が粉末ないし粒状形態である構成としているから、母材(1)の凹所(11)へ充填し易い上、その充填量の増減による改質特性の強弱調整が容易であり、また複数種の改質用材料(2)を併用して異なる特性を同時に付与することも容易になる。
【0013】
請求項4の発明では、上記請求項3の母材の局部的改質方法において、加工用ツール(3)のプローブ(32)周面にねじ(33)が刻設され、このプローブ(32)を前記ねじ(33)の進行方向に回転させながら改質用材料(2)の配置部に埋入させる構成としているから、粉末ないし粒状形態の改質用材料(2)がねじ(33)の螺旋誘導によって圧縮作用を受けながら母材(1)の流動する素材中に混ざり込むことになる。
【0014】
【発明の実施の形態】
この発明の局部的改質方法では、母材の改質を要する領域に改質用材料を配置し、この改質用材料の配置部に加工用ツールの回転子に突設されたプローブを回転しつつ埋入させて移動させる。すなわち、ここで用いる加工用ツールは既述の摩擦攪拌接合に使用されるものと同様であり、プローブを回転させながら母材に摺接させた際に、母材の素材が摩擦攪拌によって塑性流動化することにより、該プローブが母材中に埋入して且つこの埋入状態のまま母材中を移動可能となる。しかして、プローブの移動に伴い、流動化した母材の素材と改質用材料とが一体化して固化し、もって母材の上記領域に改質用材料に基づく異なった特性が付与される。
【0015】
改質対象とする母材は、特に制約はないが、一般的にはアルミニウムやその合金その他の金属材である。その改質すべき物性としては、硬さ(耐摩耗性)、電気伝導度、磁気特性、機械的強度、耐薬品性、表面粗さ等、極めて多岐にわた り、特に制約はない。また、改質を要する領域の形状、大きさ、長さ、深さ等についても制約はない。しかして、加工用ツールのプローブは、母材よりも硬い材質であればよく、単なる棒軸状でもよいが、特に改質用材料が粉末ないし粒状形態である場合には周面にねじを刻設したものが好適である。
【0016】
一方、改質用材料としては、銅,鉄,ニッケル,マンガン等の金属材料や、酸化アルミニウム,酸化クロム,炭化チタン,炭化ケイ素,窒化ケイ素等のセラミック系材料を始めとして、極めて広範な材料を特に制約なく使用でき、母材の改質すべき物性に応じて適当なものを選択すればよい。また、その形態について も、粉末、粒状物、塊状物、板材、帯板材、ブロック等、特に制約はない。
【0017】
このような改質用材料は、母材の改質を要する領域上に単に載置するだけでもよいが、埋入状態で移動するプローブとの接触によって当該改質用材料が配置位置から逃げるのを防止するために、例えば図1に示すように、母材(1)の図示一点鎖線鎖線で示す改質を要する領域(1a)に凹所(11)を設け、この凹所(11)内に、粉末、粒状物、塊状物等では充填し、板材、帯板材、ブロック等では嵌合させるのがよい。
【0018】
次に、前記の図1に示す凹所(11)を設けた母材(1)を対象とした局部的改質方法の一例について、図2〜図4を参照して説明する。
【0019】
図2(A)(B)において、(3)は加工用ツールであり、丸軸状の回転子 (31)の下端に、先端球面状で周面にねじ(33)を刻設したプローブ(3 2)が同心状に突設されており、回転駆動機構(図示省略)によって回転子(31)がプローブ(32)と一体に回転すると共に、昇降駆動機構(図示省略)によって昇降動作するようになっている。この加工用ツール(10)の下方には、母材(1)が粉末状ないし粒状の改質用材料(2)を充填した凹所(11)の一端部をプローブ(32)の直下に位置させて配置している。しかして、プローブ(32)の径及び長さは凹所(11)の幅及び深さよりも大きく設定してある。
【0020】
改質に際しては、回転子(31)を図示矢印aの如くねじ(21)の進行方向に回転しつつ下降させ、プローブ(32)を凹所(11)にかかる状態で母材 (1)中に埋入させる。これにより、凹所(11)の周辺にある母材(1)の素材が摩擦攪拌によって塑性流動化すると共に、この流動する素材中に改質用材料(2)が混ざり込む。次いで、この埋入状態のまま加工用ツール(3)を凹所 (11)に沿って移動させてゆくと、図3に示すように、回転するプローブ(32)の前方では母材(1)の素材が改質用材料(2)を混ざり込ませて流動化する一方、該プローブ(32)の後方側では流動化していた母材(1)の素材が改質用材料(2)を混ざり込ませた状態で急速に固化し、改質領域(10)が形成されてゆく。しかして、この場合、プローブ(32)がねじ(33)の進行方向に回転するため、粉末ないし粒状形態の改質用材料(2)がねじ(33)の螺旋誘導によって圧縮作用を受けながら母材(1)の流動する素材中に混ざり込むから、改質領域(10)への空気の混入が防止される。
【0021】
かくして局部的改質を施した母材(1)は、図4に示すように、その素材中に改質用材料(2)が分散状態で一体化した改質領域(10)を有し、この改質領域(10)では混在する改質用材料(2)に基づいて当該母材(1)とは異なった特性が発揮される。しかるに、当該母材(1)と改質用材料(2)とのマクロ的な接合界面は存在せず、また改質領域(10)における改質用材料(2)の混ざり込みは周辺ほど少なくなる、なだらかな分布を示すため、改質領域(10)とその周囲との間でも明確な界面を有さず、もって従来の接合による改質のような接合強度面の問題がなく、優れた耐久性が得られる。なお、改質領域(10)の上面にはガイドレール等とする浅い溝(12)が形成されている。
【0022】
また、この改質方法では、溶融法とは異なって摩擦攪拌による材料の塑性流動化が融点よりもかなり低い温度で生じ、改質領域(10)は母材(1)の素材と改質用材料(2)とが殆ど固相で混合した状態となり、溶融法のような凝固組織にはならないから、クラックの発生や熱変質を生起しにくく、両者が金属であっても金属間化合物の生成が抑制され、この金属間化合物による本来の材料性状の変質も回避される。さらに、この例では、改質領域(10)への空気の混入が防止されるから、この空気混入による脆化も回避される。
【0023】
上記例では母材(1)の改質を要する領域(1a)が直線的に連続した細長い形状であるが、該領域(1a)の形状や大きさには制約はなく、不連続であっても差し支えない。例えば該領域(1a)の幅がプローブ(32)の径より大きい場合でも、加工用ツール(3)をジグザグ状に移動させたり、位置をずらせながら往復移動させることによって対応できる。なお、改質は、通常では上記の加工用ツール(3)による加工にて完了するが、付与する特性によっては、この加工後に母材(1)の全体あるいは改質領域(10)部分に熱処理等の後処理を施してもよい。
【0024】
しかして、上記例のように、凹所(11)に配置する改質用材料(2)として粉末状ないし粒状のものを使用すれば、該凹所(11)へ充填し易い上、その充填量の増減による改質特性の強弱調整が容易であり、また複数種の改質用材料 (2)を併用して異なる特性を同時に付与することも可能となる。一方、母材 (1)の改質を要する領域(1a)が円周面等の曲面上にある場合は、改質用材料(2)が粉末状ないし粒状のものでは凹所(11)を設けても保持できないため、該凹所(11)に適嵌するように寸法設定した板状、帯板状、ブロック状等の改質用材料(2)を用いるのがよい。
【0025】
なお、上記例の改質方法では母材(1)の改質領域(10)の上面側に浅い溝(12)が形成されるが、改質領域(10)の表面を母材(1)と略同レベルに設定することも可能である。例えば、母材(1)凹所(11)に対して、図5 (A)に示すように粉末状ないし粒状の改質用材料(2)を空隙分を考慮して山盛り状態に充填したり、図6(A)に示すように該凹所(11)の容積に略等しい体積を有する帯板状の改質用材料(2)を嵌合することにより、図5及び図6の(B)に示すように形成される改質領域(10)の表面を母材(1)と略同レベルにすることができる。
【0026】
【実施例】
アルミニウムの6061−T5材からなる縦横200×100mm、厚さ4mmの母材の片面に、幅3mm、長さ80mm、深さ2mmの溝状の凹所を形成 し、この凹所内に粒子径20〜40μmの銅粉末を当該凹所の深さの約80%まで充填した。そして、図2に示す構成において長さ3mm、直径4mmで周面にねじを刻設したプローブを備える加工用ツールを使用し、その回転子を前記ねじの進行方向へ回転させつつ該プローブを上記母材の凹所の一端側に埋入させ、この埋入状態で当該ツールを凹所に沿って移動させることにより、該母材の局部的改質を行った。この母材の改質部及び非改質部のビッカース硬度(Hv)を測定したところ、改質部はHv=300、非改質部はHv=100であった。
【0027】
【発明の効果】
請求項1の発明によれば、母材の局部的改質方法として、改質部に実質的な接合界面を生じず、もって界面剥離等による耐久性の低下が防止されると共に、熱影響に起因したクラックの発生や変質による品質低下を回避できる上、加工を容易に且つ低コストで行える方法が提供される。
【0028】
請求項2の発明によれば、上記の局部的改質方法において、母材の改質を要する領域に凹所を形成し、この凹所内に改質用材料を配置するから、この改質用材料が加工中に逃げにくく、もってより確実な改質を行えるという利点がある。
【0029】
請求項3の発明によれば、母材の改質を要する領域に凹所を設ける上記の局部的改質方法において、改質用材料として粉末ないし粒状形態のものを使用することから、該凹所へ充填し易い上、改質特性の強弱調整が容易であり、また複数種の改質用材料を併用して異なる特性を同時に付与することも容易になるという利点がある。
【0030】
請求項4の発明によれば、改質用材料として粉末ないし粒状形態のものを使用する上記の局部的改質方法において、改質領域への空気の混入が防止され、この混入による脆化が回避されるという利点がある。
【図面の簡単な説明】
【図1】この発明に係る局部的改質方法の一例に適用する母材の斜視図である。
【図2】同局部的改質方法の一例における改質開始前の状態を示し、(A)は縦断側面図、(B)は縦断正面図である。
【図3】同局部的改質方法の一例における改質途上の状態を示す縦断側面図である。
【図4】同局部的改質方法の一例における改質後の母材の縦断正面図である。
【図5】同局部的改質方法の他の例に適用する母材を示し、(A)は改質開始前の縦断正面図、(B)は改質後の縦断正面図である。
【図6】同局部的改質方法の更に他の例に適用する母材を示し、(A)は改質開始前の縦断正面図、(B)は改質後の縦断正面図である。
【符号の説明】
1 ・・・母材
1a ・・・改質を要する領域
10 ・・・改質領域
11 ・・・凹所
2 ・・・改質用材料
3 ・・・加工用ツール
31 ・・・回転子
32 ・・・プローブ[0001]
BACKGROUND OF THE INVENTION
The present invention is a method for locally modifying properties of a part of a base material made of metal or the like used in various industrial fields, such as hardness, electrical conductivity, magnetic characteristics, etc. so as to be different from the base material. The present invention relates to a reforming method.
[0002]
[Prior art and its problems]
In recent years, as the manufacturing processes in various industrial fields and higher functionality of products themselves have increased, demand for materials having locally different characteristics such as hardness, electrical conductivity, and magnetic characteristics has increased. There is a demand for a product that is excellent in durability and reliability and inexpensive. However, this type of material in the past is generally in a form in which dissimilar materials having different characteristics are joined to a part of the base material, so that the joining strength is insufficient and the durability is poor. In addition, there are many problems such as the occurrence of cracks and the deterioration of the structure, resulting in a decrease in quality, and the high cost required for joining.
[0003]
For example, in an automatic production system of various factories, many guide rails are provided for operation and movement of various devices for processing and assembly, movement of workpieces, etc., as means for improving the wear resistance, In many cases, a hard metal plate different from the base metal is joined to the contact portion with the other guide rail base material. However, since there is poor adhesion between dissimilar metals, there has been a problem that the bonded interface is likely to peel off and easily rise, resulting in poor durability. Also, in pistons used in engines such as automobiles, a method of forming a piston ring part by fusing a ring-shaped dissimilar metal to the base material of the piston is often used. There was a problem that minute cracks were likely to occur in the ring portion.
[0004]
In view of the above-mentioned circumstances, this invention is a means for locally modifying a part of a base material so as to have different characteristics. An object of the present invention is to provide a method capable of preventing the deterioration of the durability, avoiding the generation of cracks due to the influence of heat and the deterioration of quality due to the alteration, and performing the processing easily and at low cost.
[0005]
[Means for Solving the Problems]
In the process of earnestly studying to achieve the above object, the inventors focused on the friction stir welding method, which has been widely used as a new joining technique in place of welding and brazing of metal materials in recent years. The application to local modification of wood was considered.
[0006]
This friction stir welding method is disclosed in, for example, Japanese Patent Application Laid-Open No. 7-505090, when a probe (rod-like material) made of a material harder than the workpiece is slidably contacted with the workpiece. Utilizing the fact that the workpiece material is plastically fluidized by the frictional heat and pressure generated at the sliding contact portion, and that the probe is embedded in the workpiece and can be moved in the workpiece in this embedded state. For example, when the probe is moved in the embedded state along the butt joint line between the metal plates, the materials of the two metal plates that are plastically flowed in front of the advancing probe are stirred and kneaded while the probes are being mixed. Since it gradually shifts to the rear side and loses frictional heat on the rear side and rapidly solidifies by cooling, both metal plates are joined together in a state where the materials are agitated and kneaded and are completely integrated.
[0007]
Therefore, the inventors have a unique idea that the plastic fluidization phenomenon of metal materials in the friction stir welding method is used for local reforming of the base material, instead of joining the general metal materials. In addition, as a result of extensive experimental research, it was found that the above-mentioned local modification can be easily performed by a simple method using the same processing tool used for the above-mentioned joining. It came.
[0008]
That is, in the method for locally reforming a base material according to the first aspect of the present invention, the material for reforming is provided in the region (1a) requiring the reforming of the base material (1), if indicated by the reference numeral in the drawing. (2) is arranged, and the probe (32) protruding from the rotor (31) of the processing tool (3) is embedded in the arrangement portion of the modifying material (2) while rotating, By moving the tool (3) along the placement portion of the modifying material (2) in this embedded state, the modifying material (by the friction agitation accompanying the rotation of the embedded probe (32) ( 2) and the base material (1) are integrated.
[0009]
In the above configuration, when the probe (32) is embedded in the placement portion of the reforming material (2), the material of the base material (1) is plastically flowed by friction stirring. The material (2) will mix and flow together. The flowing material gradually moves to the rear side of the probe (32) while being agitated and kneaded with the movement of the rotating probe (32), loses frictional heat on the rear side, and rapidly cools and solidifies. . This solidified portion is a reformed region in which the base material (1) and the reforming material (2) are kneaded and completely integrated, and have the required characteristics based on the reforming material (2). It becomes.
[0010]
Therefore, there is no bonding interface between the base material (1) and the reforming material (2), and the mixing of the reforming material (2) into the base material (1) is as close to the periphery of the solidified portion. In order to show a gentle distribution that decreases, a clear interface is not formed between the modified portion and its surroundings. Thus, in this friction stirrer, unlike the melting method, plastic fluidization of the material occurs at a temperature considerably lower than the melting point, and the solidified portion is mostly composed of the base material (1) and the reforming material (2). Since it is in a mixed state in a solid phase and is not a solidified structure as in the melting method, it is difficult for cracks and thermal alteration to occur, and even when both are metals, the formation of intermetallic compounds is suppressed.
[0011]
According to a second aspect of the present invention, in the method for locally reforming a base material according to the first aspect, a recess (11) is formed in a region where the base material (1) needs to be reformed, and the recess (11) Since the reforming material (2) is arranged on the inner surface of the base material (1), the reforming material (2) is difficult to escape from the arrangement position when the probe (32) is moved in the embedded state. The raw material and the modifying material (2) are efficiently kneaded by friction stirring.
[0012]
In the invention of
[0013]
According to a fourth aspect of the present invention, in the method for locally modifying a base material according to the third aspect, a screw (33) is formed on the peripheral surface of the probe (32) of the processing tool (3), and the probe (32). Since the screw (33) is rotated in the direction of travel of the screw (33), the reforming material (2) is embedded in the placement portion of the reforming material (2). The material is mixed into the material in which the base material (1) flows while receiving a compression action by the spiral induction.
[0014]
DETAILED DESCRIPTION OF THE INVENTION
According to the local reforming method of the present invention, a reforming material is arranged in an area where the base material needs to be reformed, and a probe projecting from a rotor of a processing tool is rotated in the reforming material arranging section. While embedding, move it. That is, the processing tool used here is the same as that used for the friction stir welding described above. When the probe is slidably contacted with the base material while rotating the probe, the material of the base material is plastically flowed by friction stirring. As a result, the probe is embedded in the base material and can be moved in the base material in the embedded state. As the probe moves, the fluidized base material and the reforming material are integrated and solidified, and thus different characteristics based on the reforming material are imparted to the region of the base material.
[0015]
The base material to be modified is not particularly limited, but is generally aluminum, its alloy, or other metal material. There are no particular restrictions on the physical properties to be modified, such as hardness (wear resistance), electrical conductivity, magnetic properties, mechanical strength, chemical resistance, and surface roughness. There are no restrictions on the shape, size, length, depth, and the like of the region requiring modification. Therefore, the probe of the processing tool may be any material that is harder than the base material and may be a simple rod shaft. However, particularly when the modifying material is in a powder or granular form, a screw is engraved on the peripheral surface. What was provided is suitable.
[0016]
On the other hand, as a material for reforming, a very wide range of materials including metal materials such as copper, iron, nickel and manganese and ceramic materials such as aluminum oxide, chromium oxide, titanium carbide, silicon carbide and silicon nitride. It can be used without particular limitation, and an appropriate one may be selected according to the physical properties of the base material to be modified. Also, there are no particular restrictions on its form, such as powder, granule, lump, plate material, strip plate material, block and the like.
[0017]
Such a reforming material may simply be placed on an area where the base material needs to be reformed, but the reforming material escapes from the placement position by contact with the probe moving in the embedded state. In order to prevent this, for example, as shown in FIG. 1, a recess (11) is provided in a region (1a) of the base material (1) that needs to be modified indicated by an alternate long and short dash line in the figure. Further, it is preferable to fill with powder, granular material, lump, etc. and fit with plate material, strip material, block or the like.
[0018]
Next, an example of the local reforming method for the base material (1) provided with the recess (11) shown in FIG. 1 will be described with reference to FIGS.
[0019]
2 (A) and 2 (B), (3) is a processing tool, which is a probe (having a tip spherical surface and a screw (33) engraved on the peripheral surface at the lower end of a round shaft rotor (31) ( 32) is concentrically provided so that the rotor (31) rotates integrally with the probe (32) by a rotation drive mechanism (not shown) and is moved up and down by a lift drive mechanism (not shown). It has become. Below the processing tool (10), one end of the recess (11) in which the base material (1) is filled with the powdery or granular modifying material (2) is positioned directly below the probe (32). It is arranged. Thus, the diameter and length of the probe (32) are set larger than the width and depth of the recess (11).
[0020]
When reforming, the rotor (31) is lowered while rotating in the direction of travel of the screw (21) as shown by the arrow a in the figure, and the probe (32) is placed in the recess (11) and the base material (1) To be embedded. Thereby, the raw material of the base material (1) around the recess (11) is plastically fluidized by friction stirring, and the modifying material (2) is mixed into the flowing raw material. Next, when the processing tool (3) is moved along the recess (11) in this embedded state, the base material (1) is located in front of the rotating probe (32) as shown in FIG. The material of the base material (1), which has been fluidized on the rear side of the probe (32), mixes the material for reforming (2). The solidified state is rapidly solidified and the modified region (10) is formed. In this case, since the probe (32) rotates in the direction of travel of the screw (33), the modifying material (2) in the powder or granular form is subjected to a compression action by the helical induction of the screw (33), and the mother Since the material (1) is mixed in the flowing material, it is possible to prevent air from entering the reforming region (10).
[0021]
Thus, the base material (1) subjected to local modification has a modified region (10) in which the modifying material (2) is integrated in a dispersed state in the material, as shown in FIG. In the modified region (10), characteristics different from those of the base material (1) are exhibited based on the mixed reforming material (2). However, there is no macroscopic bonding interface between the base material (1) and the modifying material (2), and the mixing of the modifying material (2) in the modified region (10) is less as the periphery. In order to show a gentle distribution, there is no clear interface between the modified region (10) and its surroundings, and there is no problem of the bonding strength as in the case of the modification by the conventional bonding, which is excellent. Durability is obtained. Note that a shallow groove (12) serving as a guide rail or the like is formed on the upper surface of the modified region (10).
[0022]
Further, in this reforming method, unlike the melting method, plastic fluidization of the material by friction stirring occurs at a temperature considerably lower than the melting point, and the reforming region (10) is used for the material of the base material (1) and for reforming. Since the material (2) is almost mixed in the solid phase and does not become a solidified structure as in the melting method, it is difficult for cracks and thermal alteration to occur, and even if both are metals, formation of intermetallic compounds Is suppressed, and alteration of the original material properties by this intermetallic compound is also avoided. Furthermore, in this example, since air is prevented from being mixed into the reforming region (10), embrittlement due to this air mixing is also avoided.
[0023]
In the above example, the region (1a) that requires modification of the base material (1) has a linear and continuous elongated shape, but the shape and size of the region (1a) are not limited and are discontinuous. There is no problem. For example, even when the width of the region (1a) is larger than the diameter of the probe (32), it can be dealt with by moving the processing tool (3) in a zigzag manner or reciprocating while shifting the position. The modification is usually completed by processing with the above processing tool (3). However, depending on the characteristics to be imparted, the entire base material (1) or the modified region (10) is subjected to heat treatment after the processing. A post-treatment such as the above may be performed.
[0024]
Thus, as in the above example, if a powdery or granular material is used as the modifying material (2) disposed in the recess (11), the recess (11) can be easily filled and the filling is performed. It is easy to adjust the strength of the reforming characteristics by increasing or decreasing the amount, and it is also possible to simultaneously impart different characteristics by using a plurality of kinds of reforming materials (2). On the other hand, when the region (1a) requiring modification of the base material (1) is on a curved surface such as a circumferential surface, the recess (11) is formed when the modifying material (2) is powdery or granular. Since it cannot be held even if it is provided, it is preferable to use a reforming material (2) such as a plate shape, a strip plate shape, or a block shape that is dimensioned so as to fit into the recess (11).
[0025]
In the modification method of the above example, the shallow groove (12) is formed on the upper surface side of the modified region (10) of the base material (1), but the surface of the modified region (10) is formed on the base material (1). It is also possible to set to approximately the same level. For example, as shown in FIG. 5 (A), the base material (1) recess (11) is filled with a powdery or granular reforming material (2) in a piled state in consideration of voids. As shown in FIG. 6 (A), by fitting a strip-shaped reforming material (2) having a volume substantially equal to the volume of the recess (11), (B) in FIGS. ), The surface of the modified region (10) formed can be made substantially the same level as the base material (1).
[0026]
【Example】
A groove-like recess having a width of 3 mm, a length of 80 mm, and a depth of 2 mm is formed on one side of a base material made of aluminum 6061-T5 and having a length and width of 200 × 100 mm and a thickness of 4 mm. A particle diameter of 20 mm is formed in the recess. ˜40 μm copper powder was filled to about 80% of the depth of the recess. Then, in the configuration shown in FIG. 2, a processing tool including a probe having a length of 3 mm and a diameter of 4 mm and having a screw engraved on the peripheral surface is used, and the probe is moved as described above while rotating the rotor in the advancing direction of the screw. By embedding in one end side of the recess of the base material and moving the tool along the recess in this embedded state, the base material was locally modified. When the Vickers hardness (Hv) of the modified part and the non-modified part of the base material was measured, the modified part was Hv = 300 and the non-modified part was Hv = 100.
[0027]
【The invention's effect】
According to the first aspect of the present invention, as a method for locally modifying the base material, a substantial joint interface is not generated in the reformed portion, thereby preventing a decrease in durability due to interfacial delamination and the like. There is provided a method capable of avoiding quality deterioration due to the occurrence of cracks and alteration due to cracks and easily performing the processing at low cost.
[0028]
According to the invention of
[0029]
According to the third aspect of the present invention, in the above-mentioned local reforming method in which a recess is provided in a region where the base material needs to be reformed, the material for reforming is in the form of powder or granular form. In addition, it is easy to fill in a place, and it is easy to adjust the strength of the reforming characteristics, and it is easy to simultaneously give different characteristics by using a plurality of kinds of reforming materials.
[0030]
According to the invention of claim 4, in the above-mentioned local reforming method using a powder or granular form as the reforming material, air is prevented from being mixed into the reforming region, and embrittlement due to this mixing is prevented. There is an advantage of being avoided.
[Brief description of the drawings]
FIG. 1 is a perspective view of a base material applied to an example of a local reforming method according to the present invention.
FIG. 2 shows a state before the start of reforming in an example of the local reforming method, in which (A) is a longitudinal side view, and (B) is a longitudinal front view.
FIG. 3 is a longitudinal side view showing a state during reforming in an example of the local reforming method.
FIG. 4 is a longitudinal front view of a base material after modification in an example of the local modification method.
FIG. 5 shows a base material applied to another example of the local reforming method, in which (A) is a longitudinal front view before the start of reforming, and (B) is a longitudinal front view after the reforming.
6A and 6B show a base material applied to still another example of the local reforming method, wherein FIG. 6A is a longitudinal front view before the start of reforming, and FIG. 6B is a longitudinal front view after the reforming.
[Explanation of symbols]
DESCRIPTION OF
Claims (7)
埋入した前記プローブの回転に伴う摩擦攪拌によって改質用材料と母材の素材とを固相で混合し一体化することを特徴とする母材の局部的改質方法。The reforming material is placed in an area where the base material needs to be reformed , and the tool is modified while the probe protruding from the rotor of the processing tool is rotated and embedded in the base material. By relatively moving along the arrangement part of the material for
A method for locally reforming a base material, wherein the reforming material and the base material are mixed and integrated in a solid phase by frictional stirring accompanying rotation of the embedded probe.
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP20445097A JP3775894B2 (en) | 1997-07-30 | 1997-07-30 | Method for local modification of base material |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP20445097A JP3775894B2 (en) | 1997-07-30 | 1997-07-30 | Method for local modification of base material |
Publications (2)
Publication Number | Publication Date |
---|---|
JPH1150266A JPH1150266A (en) | 1999-02-23 |
JP3775894B2 true JP3775894B2 (en) | 2006-05-17 |
Family
ID=16490736
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
JP20445097A Expired - Fee Related JP3775894B2 (en) | 1997-07-30 | 1997-07-30 | Method for local modification of base material |
Country Status (1)
Country | Link |
---|---|
JP (1) | JP3775894B2 (en) |
Families Citing this family (13)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JP4672202B2 (en) * | 2001-08-01 | 2011-04-20 | マツダ株式会社 | Rotating tool, member processing method and surface processing method using the rotating tool |
JP4335702B2 (en) * | 2004-01-22 | 2009-09-30 | 三菱重工業株式会社 | Clad material manufacturing method |
TWI335251B (en) * | 2004-03-25 | 2011-01-01 | Univ Nihon | Method ana apparatus of joining metallic plates by frictional pressure welding |
JP5052187B2 (en) * | 2006-04-11 | 2012-10-17 | 国立大学法人大阪大学 | Method for producing metal material and metal material |
JP5250410B2 (en) * | 2008-12-26 | 2013-07-31 | 株式会社日立製作所 | Manufacturing method of composite material |
JP5289990B2 (en) * | 2009-01-28 | 2013-09-11 | 日立建機株式会社 | Method for modifying the surface of a round shaft and reformer used therefor |
JP5618314B2 (en) * | 2009-03-26 | 2014-11-05 | 国立大学法人大阪大学 | Method for producing metal material and metal material |
EP3098015B1 (en) | 2011-08-19 | 2018-12-12 | Nippon Light Metal Company Ltd. | Friction stir welding method |
CN106141422A (en) * | 2016-08-23 | 2016-11-23 | 山东建筑大学 | A kind of method improving heat treatment reinforcement Aluminum Alloy Friction Stir Welding head surface corrosion resistance |
CN109676328B (en) * | 2019-02-12 | 2023-11-21 | 黄山学院 | Inclined plane workpiece surface modification method and device |
CN109648187B (en) * | 2019-02-12 | 2023-04-07 | 黄山学院 | Tool steel friction stir processing modification method and filling plate structure for modification |
CN110193658B (en) * | 2019-06-24 | 2021-03-12 | 哈尔滨工业大学 | Component-adjustable friction head capable of synchronously feeding materials and friction additive manufacturing method |
JP7432842B2 (en) * | 2019-12-04 | 2024-02-19 | 日本製鉄株式会社 | Partial composite steel material and its manufacturing method |
-
1997
- 1997-07-30 JP JP20445097A patent/JP3775894B2/en not_active Expired - Fee Related
Also Published As
Publication number | Publication date |
---|---|
JPH1150266A (en) | 1999-02-23 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
JP3775894B2 (en) | Method for local modification of base material | |
US7661575B2 (en) | Friction stirring-welding method | |
US7608296B2 (en) | Anvil for friction stir welding high temperature materials | |
JP4592103B2 (en) | Method and apparatus for joining metal plates by friction welding | |
US6892924B2 (en) | Precessing rivet and method for friction stir riveting | |
US6227432B1 (en) | Friction agitation jointing method of metal workpieces | |
KR101354488B1 (en) | Powder metal friction stir welding tool and method of manufacture thereof | |
KR20010052329A (en) | Friction stir welding tool | |
US20190061046A1 (en) | Devices, systems, and methods for increased wear resistance during low temperature friction stir processing | |
WO2001083153A1 (en) | Method of processing metal members | |
JP2007107039A (en) | Method for modifying alloy formed body and alloy formed body | |
JP2003326372A (en) | Tool for friction-stirring joining | |
JP4412608B2 (en) | Joining method and joined body | |
CN110290893A (en) | The manufacturing method of friction stirring connecting method and junction structure | |
EP1399286A1 (en) | Anvil for friction stir welding high temperature materials | |
CN106271031B (en) | Aluminum steel friction stir connecting method | |
JPH1071478A (en) | Friction agitation joining method | |
JP5953060B2 (en) | Processing method of workpiece | |
JP2011235335A (en) | Tool for friction stir welding | |
JP2006205190A (en) | Method of joining dissimilar metals | |
JP7082356B2 (en) | Friction stir welding tool and friction stir welding method | |
JP2004082144A (en) | Tool and method for friction stir welding | |
JP2000312981A (en) | Coating method of cylinder inner face | |
JP2002283070A (en) | Friction stir welding method for different kinds of metallic materials | |
JP6192040B2 (en) | Fitting manufacturing method and composite material manufacturing method |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
A521 | Written amendment |
Free format text: JAPANESE INTERMEDIATE CODE: A523 Effective date: 20040726 |
|
A621 | Written request for application examination |
Free format text: JAPANESE INTERMEDIATE CODE: A621 Effective date: 20040726 |
|
A977 | Report on retrieval |
Free format text: JAPANESE INTERMEDIATE CODE: A971007 Effective date: 20050912 |
|
A131 | Notification of reasons for refusal |
Free format text: JAPANESE INTERMEDIATE CODE: A131 Effective date: 20050927 |
|
A521 | Written amendment |
Free format text: JAPANESE INTERMEDIATE CODE: A523 Effective date: 20051125 |
|
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: 20060214 |
|
A61 | First payment of annual fees (during grant procedure) |
Free format text: JAPANESE INTERMEDIATE CODE: A61 Effective date: 20060221 |
|
R150 | Certificate of patent or registration of utility model |
Free format text: JAPANESE INTERMEDIATE CODE: R150 |
|
RD02 | Notification of acceptance of power of attorney |
Free format text: JAPANESE INTERMEDIATE CODE: R3D02 |
|
FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20120303 Year of fee payment: 6 |
|
FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20120303 Year of fee payment: 6 |
|
FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20150303 Year of fee payment: 9 |
|
LAPS | Cancellation because of no payment of annual fees |