【発明の詳細な説明】[Detailed description of the invention]
［産業上の利用分野］
本発明は、制振複合鋼板に係り、さらに詳しく
はスポツト溶接性にすぐれた制振複合鋼板に関す
るものである。
［従来の技術］
２枚の鋼板の間に樹脂層を挾持して形成した制
振複合鋼板は、その制振性能が評価されて機械、
建築等の分野へ利用範囲を拡大しつつある。
しかし上記中間樹脂層は非導電性のため、溶接
特にスポツト溶接ができず、用途が限定されてい
る。この欠点を解消するため、最近中間樹脂層の
中に導電性を有する金属粉やカーボン粉等の導電
性粒子を混入し、スポツト溶接を可能とした発明
（特開昭57−146649号）が公開されている。
また、特開昭50−79920号には、中間層に導電
性のある100メツシユより細い金属粉を１〜80vol
％含有する粘弾性物質を使用することを特徴とす
る振動吸収複合鋼板が開示されているが、特に粘
弾性物質に特徴があり主として振動吸収を目的と
する複合鋼板である。また特開昭53−128687号に
は、金属粉末を体積率で５％以上80％以下含有し
た点溶接性のすぐれた制振遮音板が開示されてい
る。
さらに特公昭60−912号には、板厚0.05mm〜1.0
mmの金属板Ａと板厚0.4mm以上の金属板Ｂとを接
着剤で接着してなる接着クラツド金属板におい
て、該接着剤層の厚みが15〜60μmであり、かつ
接着剤層中に粒径（球状でない場合はその最長
径）が使用する接着剤層厚さの0.5〜1.5倍である
金属粉を10〜100g／m2含有することを特徴とす
るスポツト溶接可能な接着クラツド金属板が開示
され、前記Ｂ板よりＡ板の方が薄いのが特徴であ
る。
［発明が解決しようとする課題］
しかしこの新しい制振複合鋼板（特開昭57−
146649号）も中間樹脂層に混入された金属粉の混
入割合が、重量パーセントで中間樹脂層の10〜50
％或いは体積％で80％にも達するため、スポツト
溶接は可能であるが、反面中間樹脂層と鋼板との
密着性が低下し、制振性能が金属粉を混入しない
通常の制振複合鋼板に比べて若干劣つている。
特に、この密着性の低下は制振複合鋼板のプレ
ス加工性を劣化させるもので、制振複合鋼板の実
用性に大きな支障となるものである。
本発明は、前記の従来の制振複合鋼板の課題を
解決するために成されたものである。
本発明は、上記密着性及び制振性能パーセント
すぐれた制振複合鋼板を得ることを目的としたも
のである。
［課題を解決するための手段］
本発明に係る制振複合鋼板は、２枚の鋼板の間
に粒度100メツシユ以下の金属粉を混入した樹脂
層を挾持してなる制振複合鋼板において、上記金
属粉が上記中間樹脂層の厚さ以下の粒径を有する
ニツケル粉を上記中間樹脂層中に２〜10重量パー
セント混入して制振複合鋼板を形成したものであ
る。
［作 用］
上記のように構成した制振複合鋼板は、鋼板と
中間樹脂層との密着性が低下せず、制振性能も通
常の制振鋼板とほぼ等しい性能を有しているに拘
らず、中間樹脂層に混入した上記ニツケル粉のた
め中間樹脂が導電性を有することとなり、スポツ
ト溶接が可能である。
前述したように制振複合鋼板において、その中
間樹脂層にニツケル粉の導電性粒子を混入する
と、密着性の良好なスポツト溶接の可能な制振複
合鋼板が得られるが、しかし反面その導電性粒子
の混入率が中間樹脂層の10重量％を超えると、鋼
板と中間樹脂層との密着性が低下し、プレス加工
性を損ない、制振複合鋼板の実用性に大きな障害
となる。
一方２重量％未満では溶接性が不良となるので
ニツケル粉の混入率を２〜10重量％に特定した。
また、ニツケル粉の導電性粒子径は、後述する
実施例に示すごとく、中間樹脂層の厚さ以下の粒
径が好ましい。
［実施例］
発明者らは、複合鋼板の構成において、先ず混
入する導電性粒子即ち金属粉の粒径が中間樹脂層
の電気伝導性に及ぼす影響を調べるため、平均粒
径が2μm，10μm，40μmのニツケル粉を用いて厚
さ100μmの中間樹脂層の厚さ方向の電気伝導度を
調べた。
第１図はその実験結果を示すもので、Ａは平均
粒径40μm，Ｂは10μm，Ｃは2μmの場合の線、σ
は電気伝導度（Ω-1cm-1）である。
図から明らかなように、粒径の大きいものほど
電気伝導度は高く、溶接に効果的であるが、制振
複合鋼板のプレス加工性や加工製品の表面性には
悪影響があるので、粒径は中間樹脂層の厚みとほ
ぼ等しいか又はそれ以下でなければならないこと
が判る。
次に金属粉の種類による導電性への影響を調べ
るため、銅粉、ニツケル粉、ステンレス粉、アル
ミニウム粉、鉄粉等について、同一粒径、同一混
入量のものとで電気伝導度を測定した。
この結果、ニツケル粉、ステンレス粉、銅粉に
ついては、高い電気伝導性を示したが、アルミニ
ウム粉、鉄粉は電気伝導性が悪かつた。
これは樹脂層に混入する時の金属粉自体の電気
伝導度がそのまま相対的に影響するものと考えら
れた。
即ち、ニツケル粉（1.4×105Ω-1・cm-1）、ステ
ンレス粉（約1.0×105Ω-1・cm-1等は酸化がほと
んどされないのに対して、アルミニウム（3.8×
105Ω-1・cm-1）、鉄粉（1.0×105Ω-1・cm-1）は酸
化被膜を形成しており、それ自体の電気伝導性を
得ることができなかつた。
また、銅粉（5.8×105Ω-1・cm-1）は酸化被膜
を形成したが、酸化銅自体が比較的高い電気伝導
度を示すのでその影響は少なかつた。
従つて、本発明に用いる金属粉自体の電気伝導
度は表面に酸化皮膜がついた状態においても、樹
脂層への混入時に、1.0×103Ω-1・cm-1以上であ
ることが好ましい。
これらのことから本発明に用いる金属粉は電気
伝導度及び抵抗の点からニツケル粉が好ましいこ
とが判る。
さらに溶接性に及ぼす金属粉の影響をみるた
め、ニツケル粉の混入量と、中間樹脂層の厚みを
変えて溶接試験を行なつた。
第２図スポツト溶接の構成図で、１は鋼板１
ａ、中間樹脂層１ｂよりなる制振複合鋼板、２は
溶接用電極である。
試験に供したサンプルは厚さ0.6mmの冷延鋼板
２枚の間に、100μm，120μm及び200μmの厚みを
有する中間樹脂層を挾持して形成された制振複合
鋼板で、中間樹脂層中へのニツケル粉混入量は、
重量パーセントで１〜10％、ニツケル粉の粒径は
最大100μm，平均40μmである。
第１表にこのスポツト溶接試験の結果を示す。
[Industrial Field of Application] The present invention relates to a vibration-damping composite steel plate, and more particularly to a vibration-damping composite steel plate with excellent spot weldability. [Prior Art] A vibration-damping composite steel plate formed by sandwiching a resin layer between two steel plates has been evaluated for its vibration-damping performance, and is used in machinery,
The scope of use is expanding to fields such as architecture. However, since the intermediate resin layer is non-conductive, it cannot be welded, especially spot welded, and its uses are limited. In order to overcome this drawback, an invention (Japanese Patent Laid-Open No. 146649/1983) has recently been published that enables spot welding by mixing conductive particles such as metal powder or carbon powder into the intermediate resin layer. has been done. In addition, in JP-A-50-79920, 1 to 80 vol of conductive metal powder thinner than 100 mesh is added to the intermediate layer.
A vibration-absorbing composite steel plate characterized by using a viscoelastic substance containing % is disclosed, but the composite steel plate is particularly characterized by the viscoelastic substance and is mainly intended for vibration absorption. Further, JP-A-53-128687 discloses a vibration damping and sound insulating plate with excellent spot weldability and containing metal powder in a volume ratio of 5% to 80%. Furthermore, Special Publication No. 60-912 has plate thicknesses of 0.05 mm to 1.0 mm.
In an adhesive clad metal plate formed by bonding a metal plate A with a thickness of 0.4 mm or more and a metal plate B with a thickness of 0.4 mm or more with an adhesive, the thickness of the adhesive layer is 15 to 60 μm, and the adhesive layer has particles in it. A spot weldable adhesive clad metal plate is characterized in that it contains 10 to 100 g/ m2 of metal powder whose diameter (the longest diameter if it is not spherical) is 0.5 to 1.5 times the thickness of the adhesive layer used. The A plate is characterized by being thinner than the B plate. [Problem to be solved by the invention] However, this new vibration-damping composite steel plate
146649), the proportion of metal powder mixed in the intermediate resin layer is 10 to 50% by weight of the intermediate resin layer.
% or volume %, spot welding is possible, but on the other hand, the adhesion between the intermediate resin layer and the steel plate decreases, and the damping performance is lower than that of a normal vibration damping composite steel plate that does not contain metal powder. It is slightly inferior in comparison. In particular, this decrease in adhesion deteriorates the press workability of the vibration-damping composite steel sheet, and is a major hindrance to the practicality of the vibration-damping composite steel sheet. The present invention has been accomplished in order to solve the problems of the conventional vibration-damping composite steel plates described above. The object of the present invention is to obtain a damping composite steel plate having excellent adhesion and damping performance. [Means for Solving the Problems] The vibration-damping composite steel plate according to the present invention is a vibration-damping composite steel plate formed by sandwiching a resin layer mixed with metal powder with a grain size of 100 mesh or less between two steel plates. A damping composite steel plate is formed by mixing 2 to 10 weight percent of nickel powder, the metal powder of which has a particle size less than the thickness of the intermediate resin layer, into the intermediate resin layer. [Function] The vibration-damping composite steel plate configured as described above does not reduce the adhesion between the steel plate and the intermediate resin layer, and has almost the same damping performance as a normal vibration-damping steel plate. First, because of the nickel powder mixed into the intermediate resin layer, the intermediate resin has conductivity, and spot welding is possible. As mentioned above, when conductive particles of nickel powder are mixed into the intermediate resin layer of a vibration-damping composite steel plate, a vibration-damping composite steel plate that has good adhesion and can be spot-welded can be obtained, but on the other hand, the conductive particles If the mixing ratio exceeds 10% by weight of the intermediate resin layer, the adhesion between the steel sheet and the intermediate resin layer will decrease, impairing press workability, and becoming a major obstacle to the practicality of vibration-damping composite steel sheets. On the other hand, if it is less than 2% by weight, weldability becomes poor, so the mixing rate of nickel powder was specified to be 2 to 10% by weight. Further, the conductive particle size of the nickel powder is preferably equal to or less than the thickness of the intermediate resin layer, as shown in the examples described later. [Example] In order to investigate the influence of the particle size of mixed conductive particles, ie, metal powder, on the electrical conductivity of the intermediate resin layer in the construction of a composite steel sheet, the inventors first investigated the influence of the particle size of mixed conductive particles, that is, metal powder, on the electrical conductivity of the intermediate resin layer. The electrical conductivity in the thickness direction of a 100 μm thick intermediate resin layer was investigated using 40 μm nickel powder. Figure 1 shows the experimental results, where A is the line for the average particle size of 40 μm, B is 10 μm, and C is the line for 2 μm.
is the electrical conductivity (Ω −1 cm −1 ). As is clear from the figure, the larger the grain size, the higher the electrical conductivity and the more effective welding, but the more the grain size It can be seen that the thickness of the intermediate resin layer must be approximately equal to or less than the thickness of the intermediate resin layer. Next, in order to investigate the effect of the type of metal powder on conductivity, we measured the electrical conductivity of copper powder, nickel powder, stainless steel powder, aluminum powder, iron powder, etc. with the same particle size and the same amount mixed in. . As a result, nickel powder, stainless steel powder, and copper powder showed high electrical conductivity, but aluminum powder and iron powder had poor electrical conductivity. This was thought to be due to the relative influence of the electrical conductivity of the metal powder itself when mixed into the resin layer. That is, nickel powder (1.4×10 5 Ω -1 cm -1 ), stainless steel powder ( approximately 1.0
10 5 Ω -1 ·cm -1 ) and iron powder (1.0×10 5 Ω -1 ·cm -1 ) formed an oxide film and could not obtain electrical conductivity by itself. Further, although the copper powder (5.8×10 5 Ω −1 ·cm −1 ) formed an oxide film, the effect was small because copper oxide itself exhibits relatively high electrical conductivity. Therefore, the electrical conductivity of the metal powder itself used in the present invention is preferably 1.0×10 3 Ω -1 cm -1 or more when mixed into the resin layer, even when an oxide film is attached to the surface. . From these facts, it can be seen that nickel powder is preferable as the metal powder used in the present invention from the viewpoint of electrical conductivity and resistance. Furthermore, in order to examine the effect of metal powder on weldability, welding tests were conducted by varying the amount of nickel powder mixed and the thickness of the intermediate resin layer. Figure 2 is a block diagram of spot welding, 1 is a steel plate 1
a, a vibration-damping composite steel plate consisting of an intermediate resin layer 1b; 2, a welding electrode; The sample used for the test was a vibration-damping composite steel plate formed by sandwiching intermediate resin layers with thicknesses of 100 μm, 120 μm, and 200 μm between two cold-rolled steel sheets with a thickness of 0.6 mm. The amount of nickel powder mixed in is
The weight percentage is 1-10%, and the particle size of the nickel powder is up to 100 μm and on average 40 μm. Table 1 shows the results of this spot welding test.
【表】
電極先端径：６mmφ，加圧力：250Kg
電流：８〜10KA，通電時間：12cycle／50Hz
（ニツケル粒子の最大粒径：100μm）
（ニツケル粒子の平均粒径：40μm）
○：良好
△：一部可能
×：不可能
第１表に示すごとく、ニツケル粉の粒径と中間
樹脂層の厚さが適当であれば、ニツケル粉の混入
量が２重量％でも溶接可能であることがわかる。
第３図、第４図にニツケル粉を混入した制振複
合鋼板の密着性をみるための実験結果を示す。
第３図及び第４図に示すごとく、ニツケル粉の
中間樹脂層への混入割合が増大し、その割合が重
量パーセントで10％を超えると、密着性を示す剪
断密着力とＴピール密着力が急速に低下すること
がわかる。
また、第５図は制振機能を表わす損失係数とニ
ツケル粉混入率との関係を示す線図であり、ニツ
ケル粉の混入による損失係数の低下は、密着力の
場合ほど著しくはないが、混入率の小さい程制振
性能は良好であることを示している。
以上の試験の結果、制振複合鋼板において、そ
の中間樹脂層中に高導電性を有し、粒径が中間樹
脂層の厚さとほぼ等しいか又はそれ以下のニツケ
ル粉を、２〜10重量パーセント混入して、制振複
合鋼板を構成すると、プレス成形性及び制振性能
ともに低下させず、しかもスポツト溶接の可能な
制振複合鋼板が得られることが判明した。
［発明の効果］
本発明は制振複合鋼板において、その中間樹脂
層中に、酸化被膜を形成し難く該中間樹脂層の厚
さ以下の粒径を有するニツケル粉を中間樹脂層の
２〜10重量％混入して制振複合鋼板を構成したの
で、通常の制振複合鋼板とほぼ同等の制振性能な
らびにプレス成形性を備え、スポツト溶接の可能
な制振複合鋼板を得ることができる。[Table] Electrode tip diameter: 6mmφ, Pressure force: 250Kg Current: 8 to 10KA, Current application time: 12cycle/50Hz (Maximum particle size of nickel particles: 100μm) (Average particle size of nickel particles: 40μm) ○: Good △: Partially Possible ×: Impossible As shown in Table 1, it can be seen that welding is possible even when the amount of nickel powder mixed is 2% by weight, as long as the particle size of the nickel powder and the thickness of the intermediate resin layer are appropriate. Figures 3 and 4 show the results of an experiment to determine the adhesion of a damping composite steel plate mixed with nickel powder. As shown in Figures 3 and 4, when the proportion of nickel powder mixed into the intermediate resin layer increases and the proportion exceeds 10% by weight, the shear adhesion force and T-peel adhesion force, which indicate adhesion, decrease. It can be seen that the value decreases rapidly. Furthermore, Fig. 5 is a diagram showing the relationship between the loss coefficient representing the vibration damping function and the nickel powder mixing rate. It is shown that the smaller the ratio, the better the damping performance. As a result of the above tests, it was found that 2 to 10% by weight of nickel powder, which has high conductivity and whose particle size is approximately equal to or smaller than the thickness of the intermediate resin layer, was added to the intermediate resin layer of the vibration-damping composite steel plate. It has been found that when a vibration-damping composite steel plate is formed by mixing these materials, a vibration-damping composite steel plate that does not deteriorate both press formability and vibration-damping performance and can be spot welded can be obtained. [Effects of the Invention] The present invention provides vibration-damping composite steel sheets in which nickel powder, which does not easily form an oxide film and has a particle size equal to or less than the thickness of the intermediate resin layer, is added to the intermediate resin layer. Since the vibration-damping composite steel plate is constructed by mixing % by weight, it is possible to obtain a vibration-damping composite steel plate that has substantially the same damping performance and press formability as a normal vibration-damping composite steel plate, and can be spot welded.
【図面の簡単な説明】[Brief explanation of the drawing]
第１図はニツケル粉混入量と電気伝導度との関
係を示す線図、第２図はスポツト溶接を示す模式
図、第３図はニツケル粉混入量と剪断密着力との
関係を示す線図、第４図はニツケル粉混入量とＴ
ピール密着力との関係を示す線図、第５図はニツ
ケル粉混入量と損失係数との関係を示す線図であ
る。
図中１は制振複合鋼板、１ａは鋼板、１ｂは中
間樹脂層、２は溶接用電極である。
Figure 1 is a diagram showing the relationship between the amount of nickel powder mixed in and electrical conductivity, Figure 2 is a schematic diagram showing spot welding, and Figure 3 is a diagram showing the relationship between the amount of nickel powder mixed in and shear adhesion force. , Figure 4 shows the amount of nickel powder mixed in and T
A diagram showing the relationship between the peel adhesion force and FIG. 5 is a diagram showing the relationship between the amount of nickel powder mixed in and the loss factor. In the figure, 1 is a damping composite steel plate, 1a is a steel plate, 1b is an intermediate resin layer, and 2 is a welding electrode.