JP3986604B2

JP3986604B2 - Metal joining method

Info

Publication number: JP3986604B2
Application number: JP03782397A
Authority: JP
Inventors: 正敏榎本; 清司田崎; 直毅西川; 武典橋本
Original assignee: Showa Denko KK
Current assignee: Showa Denko KK
Priority date: 1997-02-21
Filing date: 1997-02-21
Publication date: 2007-10-03
Anticipated expiration: 2017-02-21
Also published as: JPH10230374A

Description

【０００１】
【発明の属する技術分野】
この発明は、摩擦攪拌接合法により、金属板材、押出型材、鋳物等の金属材を突き合わせたり重ねた状態で接合する方法に関する。
【０００２】
【従来の技術】
近年、金属材の溶接やロウ付けに代わる新しい接合手段として、摩擦攪拌接合法が登場している。この接合法は、例えば特表平７−５０５０９０号公報に開示されているように、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するため、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可能になることを利用したものである。
【０００３】
例えば、図１に示すように、金属板（１）（１）同士を突き合わせて接合する場合、回転子（２）の軸心に突設されたプローブ（３）を回転させながら接合線Ｌの始端部に押し付けて埋入させ、矢印で示すように該接合線Ｌに沿って移動させる。これにより、進行するプローブ（３）の前方側では摩擦熱と圧力によって金属板（１）（１）の素材が塑性流動し、攪拌混練されながら該プローブ（３）の後方側へ漸次移行するが、この後方側では摩擦熱を失って急速に冷却固化するから、両金属板（１）（１）は素材金属が攪拌混練されて完全に一体化した状態で接合される。この場合、金属素材が塑性流動する温度は融点よりもかなり低く、接合は固相接合の範疇に入るから、接合過程を通して金属材への入熱量は溶接やロウ付けに比較して極めて少なく、接合部近傍の熱歪みによる変形や割れを生じにくく、合金の場合でも接合部の組成変化を生じないという利点がある。
【０００４】
【発明が解決しようとする課題】
しかしながら、接合対象とする金属材の表面には、油やゴミのような異物、錆等が付着していたり、樹脂塗装、メッキ、アルマイト加工等の表面処理が施されている場合があり、摩擦攪拌接合の機構状、これらの金属素材とは異なる成分が接合層中に巻き込まれる結果、接合層が素材金属とは異なった組成となって接合品位の低下を招くという問題があった。
【０００５】
この発明は、上述の事情に鑑みて、摩擦攪拌接合による金属材の接合において、接合対象とする金属材の表面の異質成分による接合品位の低下を防止する手段を提供することを目的としている。
【０００６】
【課題を解決するための手段】
上記目的を達成するために、この発明の請求項１に係る金属材の接合方法は、金属材同士の接合線に沿って回転子のプローブを埋入状態で回転しつつ進行させて両金属材同士を接合一体化する摩擦攪拌接合において、前記プローブに先行して進行する研削部材により、金属材の接合部表面を研削することを特徴とする構成を採用したものである。このような構成によれば、金属材の接合部表面の異質成分が先行する研削部材にて研削除去された上で、その部分が前記プローブによって摩擦攪拌接合されてゆくから、接合層は異質成分の巻き込みがない金属素材本来の組成を有するものとなる。
【０００７】
請求項２の発明では、上記請求項１の金属材の接合方法において、前記研削部材を回転子に取付け、該研削部材を回転子の回転によってプローブの周囲に円運動させつつ金属材の接合部表面を研削する構成を採用しているから、該研削部材を回転させるための駆動軸を別途に設ける必要がない。
【０００８】
請求項３の発明では、上記請求項１の金属材の接合方法において、前記研削部材を回転子の取付け基体に保持された当該回転子とは別体の回転駆動軸の先端に設け、該研削部材を回転子と共に金属材同士の接合線に沿って進行させる構成を採用しているから、金属表面の異質成分の状態や金属素材の種類に応じて研削部材の回転速度を調整できる。
【０００９】
【発明の実施の形態】
以下、この発明に係る金属材の接合方法について、図面を参照して具体的に説明する。
【００１０】
図２は第一実施例に使用する回転子（２Ａ）を示す。この回転子（２Ａ）は、丸軸部（２１）の下端に丸棒状で球面先端を有するプローブ（３）が同心状に突設されると共に、丸軸部（２１）の周面上部に複数個のブラケット（４）・・が周方向に等配形成され、各ブラケット（４）には枢支ピン（４ａ）を介してロッド（５）が上端で垂直面内揺動自在に枢着されている。しかして、各ロッド（５）は、下端には砥石等よりなる研削部材（６Ａ）を保持すると共に、その中間部と丸軸部（２１）の周面に設けた係止突片（２２）との間にコイルスプリング（７）が係着しており、回転子（３Ａ）の静止状態下で下端側が若干外側へ出るように傾斜し、且つ下端がプローブ（３）の上下端の間の高さになるように設定されている。
【００１１】
図３はアルミニウム材等の金属板（１）（１）の突き合わせ部（１０）を上記回転子（２Ａ）を用いて摩擦攪拌接合する状態を示す。これら金属板（１）（１）の表面にはアルマイト加工等による酸化膜（１１）を有しているが、回転子（２Ａ）を回転させつつプローブ（３）を突き合わせ部（１０）に埋入させた際に、各ロッド（５）は下端の研削部材（６Ａ）が金属板（１）（１）の表面に当接し、コイルスプリング（７）の付勢に抗して外側への開き出しを大きくし、この状態で研削部材（６Ａ）が回転子（２Ａ）の回転と共にプローブ（３）を中心として円運動を行い、金属板（１）（１）の表面を研削する。
【００１２】
従って、回転子（２Ａ）を矢印ａのように突き合わせ部（１０）に沿って進行させてゆくと、プローブ（３）の進行方向の前方では、円運動する研削部材（６Ａ）が常に先行して金属板（１）（１）の表面を研削し、これに伴って酸化膜（１１）が除去されるから、該プローブ（３）による摩擦攪拌接合は常に酸化膜（１１）のない領域で行われ、金属素材のみからなる接合層（１２）が形成されてゆく結果、高い接合品位が得られる。なお、研削部材（６Ａ）による研削粉は、適当なブロアーを設けて吹き飛ばすか、もしくはダクトで吸引して除去すればよい。
【００１３】
図４は、この発明の第二実施例を示す。この場合、回転子（２Ｂ）の取付け基体（２０）に、回転子（２Ｂ）とは独立した回転駆動軸（８）が垂設され、この回転駆動軸（８）の下端に砥石等よりなる研削部材（６Ｂ）が取付けられている。そして、摩擦攪拌接合に際し、回転子（２Ａ）を回転させつつプローブ（３）を突き合わせ部（１０）に埋入させ、基体（２０）を矢印ａのように突き合わせ部（１０）に沿って進行させてゆくと、先行する回転駆動軸（８）の研削部材（６Ｂ）がプローブ（３）の進行方向の前方において金属板（１）（１）の表面を研削して酸化膜（１１）を除去するから、前記第一実施例と同様に摩擦攪拌接合は常に酸化膜（１１）のない領域で行われ、金属素材のみからなる接合層（１２）が形成され、高い接合品位が得られる。なお、研削粉の除去は、前記同様にブロアやダクトにて除去すればよい。
【００１４】
この第二実施例の構成では、回転駆動軸（８）の回転速度を回転子（２Ｂ）とは独立して設定可能であるから、研削部材（６Ｂ）による研削力を酸化膜（１１）の厚み、硬さ、金属板（１）の素材の種類、接合速度等に応じて適当に調整できる。
【００１５】
なお、上記第一及び第二実施例では、金属板（１）の表面に酸化膜（１１）を有する場合について述べたが、この酸化膜（１１）に限らず、樹脂塗膜やメッキ層の如き他の表面処理による異質層が存在したり、油やゴミのような異物、錆等が付着している場合でも、これら異質成分を同様の研削によって除去し、もって金属素材のみからなる接合層（１２）を形成できる。また、クラッド板等の積層体を接合対象とし、接合部分で異なる層の成分が混じり合うことを嫌う場合でも、接合領域における不要層を同様の研削によって除去して摩擦攪拌接合を行うことができる。
【００１６】
この発明では、前記第一実施例のように研削部材を回転子に取付ける構成において、該研削部材の材質、形状、取付け構造、取付け数、金属材表面への押圧手段等、細部構成は種々設計変更可能である。一方、第二実施例のように回転子の取付け基体の回転駆動軸に研削部材を設ける構成でも、該研削部材の材質、形状、取付け構造、金属材表面への押圧手段等、細部構成は種々設計変更可能である。更に、摩擦攪拌接合においてプローブを接合線に沿って進行させるには、回転子側と金属材側の何れかを移動させればよい。また、摩擦攪拌接合は金属材同士の突き合わせ部に限らず、重ね部やかみ合わせ部でも同様に行える。
【００１７】
【発明の効果】
請求項１の発明によれば、摩擦攪拌接合による金属材の接合方法において、金属材の接合部表面に油やゴミのような異物、錆等が付着していたり、樹脂塗装、メッキ、アルマイト加工等の表面処理が施されている場合でも、これら異質成分が常に回転子のプローブの進行方向前方側で先行して研削除去されるから、接合層が異質成分を含まない金属素材本来の組成を有するものとなり、高い接合品位が得られる。
【００１８】
請求項２の発明によれば、上記の接合方法において、異質成分を除去する研削部材が回転子に取付けられているから、該研削部材を回転させるための駆動軸を別途に設ける必要がなく、それだけ設備が簡素化してコスト低減に繋がるという利点がある。
【００１９】
請求項３の発明によれば、上記の接合方法において、異質成分を除去する研削部材が回転子とは別体の回転駆動軸に設けられるから、金属表面の除去すべき異質成分の状態や金属素材の種類に応じて研削部材の回転速度を調整できるという利点がある。
【図面の簡単な説明】
【図１】摩擦攪拌接合による金属材の接合状況を示す斜視図である。
【図２】この発明に係る金属材の接合方法の第一実施例に使用する回転子の側面図である。
【図３】同第一実施例の接合方法を示す縦断側面図である。
【図４】同第二実施例の接合方法を示す縦断側面図である。
【符号の説明】
１…金属板（金属材）
１０…突き合わせ部
１１…酸化膜
１２…接合層
２，２Ａ，２Ｂ…回転子
２０…取付け基体
３…プローブ
５…ロッド
６Ａ，６Ｂ…研削部材
７…コイルスプリング
８…回転駆動軸
Ｌ…接合線[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a method of joining metal materials such as a metal plate material, an extrusion mold material, and a casting in a state of being butted or overlapped by a friction stir welding method.
[0002]
[Prior art]
In recent years, a friction stir welding method has appeared as a new joining means that replaces welding and brazing of metal materials. This joining method is, for example, as disclosed in Japanese Patent Publication No. 7-505090, when a probe made of a material harder than the workpiece (rod-like object) is slidably contacted with the workpiece, Because the workpiece material is plastically fluidized by the frictional heat and pressure generated at the sliding contact part, the probe is embedded in the workpiece and can be moved through the workpiece in this embedded state. It is a thing that makes use of.
[0003]
For example, as shown in FIG. 1, when the metal plates (1) and (1) are butted together and joined, the probe line (3) protruding from the axis of the rotor (2) is rotated while the joint line L is rotated. It is pressed against the start end to be embedded, and moved along the joining line L as indicated by an arrow. As a result, the material of the metal plates (1) (1) plastically flows by frictional heat and pressure on the front side of the traveling probe (3), and gradually moves to the rear side of the probe (3) while being stirred and kneaded. Since the rear side loses frictional heat and rapidly cools and solidifies, the two metal plates (1) and (1) are joined together in a state where the raw metals are agitated and kneaded and are completely integrated. In this case, the temperature at which the metal material plastically flows is much lower than the melting point, and joining is in the category of solid phase joining, so the amount of heat input to the metal material throughout the joining process is extremely small compared to welding and brazing, There is an advantage that deformation and cracking due to thermal strain in the vicinity of the joint are unlikely to occur, and even in the case of an alloy, there is no change in the composition of the joint.
[0004]
[Problems to be solved by the invention]
However, the surface of the metal material to be joined may have foreign matters such as oil or dust, rust, etc., or may have been subjected to surface treatment such as resin coating, plating, anodizing, etc. As a result of the mechanical shape of the stir welding and components different from these metal materials being involved in the bonding layer, there is a problem that the bonding layer has a composition different from that of the material metal, leading to a decrease in bonding quality.
[0005]
In view of the above-described circumstances, an object of the present invention is to provide means for preventing deterioration in joining quality due to foreign components on the surface of a metal material to be joined in joining of metal materials by friction stir welding. .
[0006]
[Means for Solving the Problems]
In order to achieve the above object, a metal material joining method according to claim 1 of the present invention is such that a probe of a rotor is advanced while rotating in an embedded state along a joining line between metal materials, and both metal materials are used. In the friction stir welding in which the members are joined and integrated, a configuration is employed in which the surface of the joint portion of the metal material is ground by a grinding member that proceeds prior to the probe. According to such a configuration, the foreign component on the surface of the joint portion of the metal material is ground and removed by the preceding grinding member, and the portion is friction stir welded by the probe. It has the original composition of the metal material without any entrainment.
[0007]
According to a second aspect of the present invention, in the metal material joining method according to the first aspect, the grinding member is attached to a rotor, and the grinding member is circularly moved around the probe by the rotation of the rotor. Since the structure for grinding the surface is adopted, there is no need to provide a separate drive shaft for rotating the grinding member.
[0008]
According to a third aspect of the present invention, in the metal material joining method according to the first aspect, the grinding member is provided at a tip of a rotary drive shaft that is separate from the rotor held by a mounting base of the rotor. Since the structure which advances a member along the joining line of metal materials with a rotor is employ | adopted, the rotational speed of a grinding member can be adjusted according to the state of the foreign component of a metal surface, and the kind of metal raw material.
[0009]
DETAILED DESCRIPTION OF THE INVENTION
The metal material joining method according to the present invention will be specifically described below with reference to the drawings.
[0010]
FIG. 2 shows the rotor (2A) used in the first embodiment. The rotor (2A) has a round rod-like probe (3) projecting concentrically at the lower end of the round shaft (21), and a plurality of the rotor (2A) at the upper part of the circumferential surface of the round shaft (21). A plurality of brackets (4) are equally formed in the circumferential direction, and a rod (5) is pivotally attached to each bracket (4) via a pivot pin (4a) so as to be swingable in a vertical plane at the upper end. ing. Thus, each rod (5) holds a grinding member (6A) made of a grindstone or the like at the lower end, and a locking projection piece (22) provided on the peripheral surface of the intermediate portion and the round shaft portion (21). The coil spring (7) is engaged with the rotor (3A), and the rotor (3A) is inclined so that the lower end side slightly protrudes outwardly, and the lower end is between the upper and lower ends of the probe (3). It is set to be height.
[0011]
FIG. 3 shows a state in which the butted portion (10) of the metal plate (1) (1) such as an aluminum material is friction stir welded using the rotor (2A). The surface of these metal plates (1) (1) has an oxide film (11) formed by anodizing or the like, but the probe (3) is buried in the butting part (10) while rotating the rotor (2A). When the rod (5) is inserted, the grinding member (6A) at the lower end contacts the surface of the metal plate (1) (1), and the rod (5) opens outward against the bias of the coil spring (7). In this state, the grinding member (6A) performs a circular motion around the probe (3) along with the rotation of the rotor (2A) to grind the surface of the metal plates (1) (1).
[0012]
Therefore, when the rotor (2A) is advanced along the abutting portion (10) as indicated by an arrow a, the circularly moving grinding member (6A) always precedes in the forward direction of the probe (3). Then, the surface of the metal plate (1) (1) is ground, and the oxide film (11) is removed accordingly. Therefore, the friction stir welding by the probe (3) is always performed in a region where the oxide film (11) is not present. As a result of the formation of the bonding layer (12) made of only the metal material, a high bonding quality is obtained. Note that the grinding powder from the grinding member (6A) may be blown off by providing an appropriate blower or may be removed by suction through a duct.
[0013]
FIG. 4 shows a second embodiment of the present invention. In this case, a rotation drive shaft (8) independent of the rotor (2B) is suspended from the mounting base (20) of the rotor (2B), and a lower end of the rotation drive shaft (8) is made of a grindstone or the like. A grinding member (6B) is attached. Then, during the friction stir welding, the probe (3) is embedded in the abutting portion (10) while rotating the rotor (2A), and the base (20) advances along the abutting portion (10) as indicated by an arrow a. As a result, the grinding member (6B) of the preceding rotary drive shaft (8) grinds the surface of the metal plate (1) (1) in front of the traveling direction of the probe (3) to form the oxide film (11). Therefore, as in the first embodiment, the friction stir welding is always performed in the region without the oxide film (11), and the bonding layer (12) made of only the metal material is formed, so that a high bonding quality is obtained. In addition, what is necessary is just to remove a grinding | polishing powder with a blower or a duct similarly to the above.
[0014]
In the configuration of the second embodiment, the rotational speed of the rotary drive shaft (8) can be set independently of the rotor (2B), so that the grinding force by the grinding member (6B) is changed to the oxide film (11). The thickness, hardness, metal plate (1) material type, bonding speed, etc. can be adjusted appropriately.
[0015]
In the first and second embodiments, the case where the surface of the metal plate (1) has the oxide film (11) has been described. However, the present invention is not limited to the oxide film (11), and the resin coating film and the plating layer Even if there is a foreign layer due to other surface treatments such as this, or foreign matter such as oil or dust, rust, etc. are attached, these foreign components are removed by the same grinding, so that the joining layer consists only of metal material (12) can be formed. In addition, even when a laminated body such as a clad plate is to be bonded and it is difficult to mix components of different layers at the bonded portion, unnecessary layers in the bonded region can be removed by similar grinding to perform friction stir welding. it can.
[0016]
In the present invention, in the configuration in which the grinding member is attached to the rotor as in the first embodiment, the detailed configuration such as the material of the grinding member, the shape, the mounting structure, the number of mountings, the pressing means to the metal material surface, etc. are variously designed. It can be changed. On the other hand, even if the grinding member is provided on the rotational drive shaft of the mounting base of the rotor as in the second embodiment, the detailed construction of the grinding member material, shape, mounting structure, means for pressing the metal material surface, etc. Various design changes are possible. Furthermore, in order to advance the probe along the joining line in the friction stir welding, it is only necessary to move either the rotor side or the metal material side. Further, the friction stir welding is not limited to the abutting portion between the metal materials, but can be similarly performed in the overlapping portion or the engaging portion.
[0017]
【The invention's effect】
According to the first aspect of the present invention, in the method for joining metal materials by friction stir welding, foreign materials such as oil and dust, rust, etc. are attached to the surface of the joint portion of the metal material, resin coating, plating, anodizing processing Even when surface treatment such as the above is applied, these extraneous components are always ground and removed in front of the traveling direction of the probe of the rotor, so that the bonding layer has the original composition of the metal material that does not contain extraneous components. Therefore, high bonding quality can be obtained.
[0018]
According to the invention of claim 2, in the above joining method, since the grinding member for removing the foreign component is attached to the rotor, there is no need to separately provide a drive shaft for rotating the grinding member, There is an advantage that the equipment is simplified and the cost is reduced.
[0019]
According to the invention of claim 3, in the above-mentioned joining method, since the grinding member for removing the foreign component is provided on the rotary drive shaft separate from the rotor, the state of the foreign component to be removed from the metal surface and the metal There is an advantage that the rotational speed of the grinding member can be adjusted according to the type of material.
[Brief description of the drawings]
FIG. 1 is a perspective view showing a joining state of metal materials by friction stir welding.
FIG. 2 is a side view of a rotor used in a first embodiment of a method for joining metal materials according to the present invention.
FIG. 3 is a longitudinal side view showing the joining method of the first embodiment.
FIG. 4 is a longitudinal side view showing a joining method of the second embodiment.
[Explanation of symbols]
1 ... Metal plate (metal material)
DESCRIPTION OF SYMBOLS 10 ... Butting part 11 ... Oxide film 12 ... Joining layer 2,2A, 2B ... Rotor 20 ... Mounting base 3 ... Probe 5 ... Rod 6A, 6B ... Grinding member 7 ... Coil spring 8 ... Rotation drive shaft L ... Joining line

Claims

In friction stir welding, in which both the metal materials are joined and integrated by advancing while rotating the probe of the rotor along the joining line between the metal materials,
A probe protrudes concentrically at the lower end of the round shaft portion of the rotor, and a rod for holding a grinding member at the lower end of the bracket formed on the upper peripheral surface of the round shaft portion has a vertical surface at the upper end. A coil spring is engaged between an intermediate portion of the rod and a locking projection provided on the peripheral surface of the round shaft portion, and is pivotally attached to the inner shaft so that the rotor is stationary when the rotor is stationary. Using a joining device that is set so that the lower end side of the rod is inclined outward and the lower end is set to a height between the upper and lower ends of the probe,
A method for joining metal materials, characterized in that a grinding member of the joining device is circularly moved around a probe by rotation of a rotor to grind a surface of a joint portion of the metal material prior to the probe.

The metal material joining method according to claim 1, wherein the metal material is a surface-treated metal material.

The metal material joining method according to claim 2, wherein the surface treatment is any one of resin coating, plating, and alumite processing.

The metal material joining method according to claim 1, wherein the metal material is an aluminum material.

The metal material joining method according to claim 1, wherein the grinding powder is removed.

A probe protrudes concentrically at the lower end of the round shaft portion of the rotor, and a rod that holds a grinding member at the lower end is in a vertical plane at the upper end of the bracket formed on the upper peripheral surface of the round shaft portion. A coil spring is engaged between an intermediate portion of the rod and a locking projection provided on the peripheral surface of the round shaft portion, and the rod is supported in a stationary state of the rotor. An apparatus for joining metal materials, wherein the lower end side of the metal plate is inclined so as to protrude outward, and the lower end is set to a height between the upper and lower ends of the probe.