JPH0468264B2 - - Google Patents
Info
- Publication number
- JPH0468264B2 JPH0468264B2 JP29023685A JP29023685A JPH0468264B2 JP H0468264 B2 JPH0468264 B2 JP H0468264B2 JP 29023685 A JP29023685 A JP 29023685A JP 29023685 A JP29023685 A JP 29023685A JP H0468264 B2 JPH0468264 B2 JP H0468264B2
- Authority
- JP
- Japan
- Prior art keywords
- metal
- intermediate layer
- ceramics
- base material
- layer
- 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
Links
- 229910052751 metal Inorganic materials 0.000 claims description 84
- 239000002184 metal Substances 0.000 claims description 84
- 239000000919 ceramic Substances 0.000 claims description 39
- 239000000463 material Substances 0.000 description 25
- 230000008602 contraction Effects 0.000 description 7
- 238000000034 method Methods 0.000 description 7
- 238000005219 brazing Methods 0.000 description 5
- 229910045601 alloy Inorganic materials 0.000 description 4
- 239000000956 alloy Substances 0.000 description 4
- 229910052802 copper Inorganic materials 0.000 description 4
- 239000010949 copper Substances 0.000 description 4
- RYGMFSIKBFXOCR-UHFFFAOYSA-N Copper Chemical compound [Cu] RYGMFSIKBFXOCR-UHFFFAOYSA-N 0.000 description 3
- 230000000694 effects Effects 0.000 description 3
- 229910000831 Steel Inorganic materials 0.000 description 2
- 230000007423 decrease Effects 0.000 description 2
- 230000006866 deterioration Effects 0.000 description 2
- 150000002739 metals Chemical class 0.000 description 2
- 239000010959 steel Substances 0.000 description 2
- 229910018072 Al 2 O 3 Inorganic materials 0.000 description 1
- -1 Fe-Ni-Co alloys Chemical class 0.000 description 1
- 244000126211 Hericium coralloides Species 0.000 description 1
- 229910001030 Iron–nickel alloy Inorganic materials 0.000 description 1
- 229910017709 Ni Co Inorganic materials 0.000 description 1
- 229910003267 Ni-Co Inorganic materials 0.000 description 1
- 229910003262 Ni‐Co Inorganic materials 0.000 description 1
- 229910052782 aluminium Inorganic materials 0.000 description 1
- PNEYBMLMFCGWSK-UHFFFAOYSA-N aluminium oxide Inorganic materials [O-2].[O-2].[O-2].[Al+3].[Al+3] PNEYBMLMFCGWSK-UHFFFAOYSA-N 0.000 description 1
- 230000000052 comparative effect Effects 0.000 description 1
- 238000001816 cooling Methods 0.000 description 1
- 238000009792 diffusion process Methods 0.000 description 1
- 238000002474 experimental method Methods 0.000 description 1
- 238000010438 heat treatment Methods 0.000 description 1
- 229910052750 molybdenum Inorganic materials 0.000 description 1
- 229910052759 nickel Inorganic materials 0.000 description 1
- 229910000510 noble metal Inorganic materials 0.000 description 1
- 229910052721 tungsten Inorganic materials 0.000 description 1
Landscapes
- Pressure Welding/Diffusion-Bonding (AREA)
- Ceramic Products (AREA)
Description
【発明の詳細な説明】
〔産業上の利用分野〕
この発明は、金属とセラミツクスとが接合され
てなる金属−セラミツクス接合部材に関するもの
である。DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a metal-ceramic bonding member formed by bonding a metal and a ceramic.
周知のように、摩耗や熱作用を頻繁に受ける金
属部品（金属母材）に対しては、一部にセラミツ
クスを用いて部品の耐摩耗性耐熱性の向上を図る
手段がとられている。
As is well known, for metal parts (metal base material) that are frequently subjected to wear and heat effects, measures have been taken to improve the wear resistance and heat resistance of parts by using ceramics in some parts.
従来、上記のような金属−セラミツクス接合部
材は、第５図に示すように、金属母材１とセラミ
ツクス２とを金属中間層３を介して接合一体化し
たものであつた。この接合部材の接合方法として
は、主に次の３つの方法が用いられている。ま
ず、第１の方法は、セラミツクス２の接合面に予
め30〜60μm程度の厚みの金属薄層（メタライジ
ング層）を形成しておき、このセラミツクス２に
前記金属中間層３をロウ付するとともに、この金
属中間層３を金属母材１にロウ付する方法であ
る。また、第２の方法は、金属母材１の接合面に
は金属用のロウ材を塗布するとともに、セラミツ
クス２にはメタライズ用のロウ材を塗布し、これ
らの間に金属中間層３を介装し、これらを加熱す
ることによつてロウ付、一体化する方法である。
そして、第３の方法は、金属母材１とセラミツク
ス２との間に金属中間層３を介装し、これら３者
を加圧下で加熱し、金属中間層３をそれぞれ金属
母材１およびセラミツクス２中に拡散させ、接合
する方法である。 Conventionally, the metal-ceramic bonding member as described above has been made by integrally bonding a metal base material 1 and a ceramic 2 via a metal intermediate layer 3, as shown in FIG. The following three methods are mainly used to join the joining members. First, in the first method, a thin metal layer (metallizing layer) with a thickness of about 30 to 60 μm is formed in advance on the bonding surface of the ceramic 2, and the metal intermediate layer 3 is brazed to the ceramic 2. In this method, this metal intermediate layer 3 is brazed to the metal base material 1. In addition, in the second method, a metal brazing material is applied to the bonding surface of the metal base material 1, and a metallizing brazing material is applied to the ceramics 2, with a metal intermediate layer 3 interposed between them. This is a method of brazing and integrating these by heating them.
In the third method, a metal intermediate layer 3 is interposed between the metal base material 1 and the ceramics 2, these three are heated under pressure, and the metal intermediate layer 3 is interposed between the metal base material 1 and the ceramics 2, respectively. This is a method of diffusion and bonding into 2.
上記金属中間層３としては、Cu，Al，Niや、
またはAg等の貴金属、そして、これら単体金属
を含んでなる軟質合金、また、Fe・Ni・Co合
金、Fe・Ni合金、Ｗ，Mo等の合金あるいは単体
の低熱膨張金属が使用されている。 The metal intermediate layer 3 may include Cu, Al, Ni,
Or noble metals such as Ag, soft alloys containing these single metals, alloys such as Fe-Ni-Co alloys, Fe-Ni alloys, W, Mo, etc., or single low thermal expansion metals are used.
上記接合構造において、接合強度はセラミツク
ス２と金属中間層３との接合面積に比例すること
が知られている。また、金属母材１とセラミツク
ス２との間にかかる応力を緩和するためには、金
属中間層３としてはある程度以上の厚みが必要で
あるが、金属中間層３自体の伸縮に伴なう変形力
のセラミツクス２への影響を考える場合、この金
属中間層３の厚みは薄い方が好ましいことにな
る。従つて、現状において、セラミツクス２に直
接接合しているメタライジング層などは上記した
ように30〜60μm程度の薄さに形成されている。 In the above bonding structure, it is known that the bonding strength is proportional to the bonding area between the ceramics 2 and the metal intermediate layer 3. In addition, in order to alleviate the stress applied between the metal base material 1 and the ceramics 2, the metal intermediate layer 3 needs to have a certain thickness or more, but deformation due to expansion and contraction of the metal intermediate layer 3 itself When considering the influence of force on the ceramics 2, it is preferable that the metal intermediate layer 3 be thinner. Therefore, at present, the metallizing layer and the like directly bonded to the ceramics 2 are formed to be as thin as 30 to 60 μm, as described above.
ところで、上記従来の金属−セラミツクス接合
部材には、下記のような問題点があり、その解決
が望まれている。
By the way, the above-mentioned conventional metal-ceramic bonding members have the following problems, and solutions to these problems are desired.
すなわち、上記接合部材においては、第６図に
示すように、通常は接合強度を上げるためにセラ
ミツクス２の接合側の面２ａにおける接合面のほ
ぼ全域を覆うように金属中間層３を形成し、接合
している。ところが、このような構造において
は、例えば熱膨張率の大きい金属母材１の冷却収
縮に伴つて金属中間層３にかかる引張り応力は、
図中矢印のように各辺の中央ないし接合面中央に
向つて働くことになり、その結果、金属中間層３
の角部Ｃ…に最も大きな引張り応力が働く。その
ため、引張り応力に対して弱いセラミツクス２
は、上記角部Ｃに相当する部分に応力集中が生じ
てクラツクが発生し、剥離してしまうことがしば
しば発生している。 That is, in the above bonding member, as shown in FIG. 6, a metal intermediate layer 3 is usually formed so as to cover almost the entire bonding surface on the bonding side surface 2a of the ceramics 2 in order to increase the bonding strength. It is joined. However, in such a structure, for example, the tensile stress applied to the metal intermediate layer 3 due to cooling contraction of the metal base material 1 having a large coefficient of thermal expansion is
As shown by the arrows in the figure, the metal intermediate layer 3 acts toward the center of each side or the center of the joint surface.
The largest tensile stress acts on the corner C... Therefore, ceramics 2 are weak against tensile stress.
In this case, stress concentration occurs in the portion corresponding to the corner C, which often causes cracks and peeling.
これに対し、第７図に示すように、応力集中を
避けるために接合部分４に角部をつくらないよう
に金属中間層３の形状を円板状とする構造が考え
られる。しかし、例えば、Al2O3の熱膨張率は7.8
×10-6，SiN4のそれは４×10-6であり、鋼材のそ
れは14〜17×10-6というように、金属母材の熱膨
張率はセラミツクスの２〜４倍もあるため、角部
のない接合面の採用によつて接合面積をある程度
減少して、換言すれば接合強度をある程度犠牲に
して行なう上記改良構造においても、第８図に示
すように、経時的に接合部分の外周に沿つてセラ
ミツクス２にクラツクが発生し、終には剥離して
しまうという劣化現象を避けることができない。
特に、金属母材が外部からの熱や機械的外力を受
け、大きな変形を伴う場合は、一層セラミツクス
に力が加わり、クラツクが発生しやすい。 On the other hand, as shown in FIG. 7, a structure can be considered in which the metal intermediate layer 3 is shaped like a disk so that no corners are formed in the joint portion 4 in order to avoid stress concentration. However, for example, the coefficient of thermal expansion of Al 2 O 3 is 7.8
×10 -6 , that of SiN 4 is 4 × 10 -6 , and that of steel is 14 to 17 × 10 -6.The coefficient of thermal expansion of the metal base material is 2 to 4 times that of ceramics, so Even in the above-mentioned improved structure in which the joint area is reduced to some extent by adopting a joint surface with no parts, in other words, the joint strength is sacrificed to some extent, as shown in Figure 8, the outer periphery of the joint part decreases over time. It is impossible to avoid a deterioration phenomenon in which cracks occur in the ceramic 2 along the surface and eventually it peels off.
In particular, when the metal base material is subjected to external heat or external mechanical force and undergoes large deformation, the force is even more applied to the ceramics, making it more likely that cracks will occur.
この発明は上記事情に鑑みてなされたもので、
その目的は金属母材の熱的伸縮や外力に伴う変形
力がセラミツクスにかかるのを減少させ、それに
よりセラミツクスのクラツクを減少させ、製品の
信頼性の向上および高寿命化を図ることのできる
金属−セラミツクス接合部材を提供することにあ
る。 This invention was made in view of the above circumstances,
The purpose of this is to reduce the deformation force that is applied to ceramics due to the thermal expansion and contraction of the metal base material and external forces, thereby reducing cracks in ceramics and improving the reliability and longevity of products. - To provide a ceramic bonding member.
この発明に係る金属−セラミツクス接合部材
は、金属中間層の中間またはこの金属中間層と金
属母材との間に金属母材の熱的伸縮あるいは外力
による変形力を吸収する緩衝金属層を介装し、一
体化されていることを特徴とするものである。
The metal-ceramic bonding member according to the present invention has a buffer metal layer interposed between the metal intermediate layer or between the metal intermediate layer and the metal base material to absorb deformation force due to thermal expansion and contraction of the metal base material or external force. It is characterized by being integrated.
上記緩衝金属層としては、金属をメツシユ状、
くし歯状、束線状などの伸縮形状にしたものが採
用される。なお、束線状とは、ワイヤ状部材を間
欠的または連続的に間隔を置いて配列した構造体
を示すものである。 The buffer metal layer is made of metal in a mesh shape,
Those with an expandable shape such as a comb tooth shape or a bundle wire shape are used. Note that the wire-like structure refers to a structure in which wire-like members are arranged intermittently or continuously at intervals.
上記構成の本発明接合部材によれば、金属母材
に生じる強い伸縮に伴う変形力は、金属母材に直
接または金属中間層を介して一体化されている緩
衝金属層により吸収もしくは軽減され、セラミツ
クスへの負荷を軽減するので、接合されたセラミ
ツクスにおけるクラツクなどの劣化を減少させ
る。 According to the bonding member of the present invention having the above configuration, the deformation force caused by strong expansion and contraction occurring in the metal base material is absorbed or reduced by the buffer metal layer that is integrated with the metal base material directly or via a metal intermediate layer, Since the load on the ceramics is reduced, deterioration such as cracks in the bonded ceramics is reduced.
以下、本発明を実施例によりさらに詳しく説明
する。 Hereinafter, the present invention will be explained in more detail with reference to Examples.
〔実施例 １〜３〕
実施例１は、第１図に示すように、くし歯を有
する板状金属を緩衝金属層５としたもので、この
緩衝金属層５が金属母材１に接合されている金属
中間層３ａと、セラミツクス２に接合されている
金属中間層３ｂとにロウ付されてなるものであ
る。[Examples 1 to 3] In Example 1, as shown in FIG. 1, the buffer metal layer 5 is made of a sheet metal having comb teeth, and the buffer metal layer 5 is bonded to the metal base material 1. The metal intermediate layer 3a is bonded to the ceramic 2, and the metal intermediate layer 3b is bonded to the ceramic 2 by brazing.
実施例２は、第２図に示すように、上記実施例
１のくし歯状の緩衝金属層５のかわりにワイヤを
所定間隔を置いた束線状部材を緩衝金属層６とし
たものであり、上記実施例１同様にこの緩衝金属
層６は金属中間層３ａ，３ｂにロウ付されてなる
ものである。 In Example 2, as shown in FIG. 2, instead of the comb-like buffer metal layer 5 of Example 1, the buffer metal layer 6 is a wire bundle member in which wires are spaced at predetermined intervals. As in the first embodiment, this buffer metal layer 6 is brazed to the metal intermediate layers 3a and 3b.
実施例３は、第３図に示すように、上記各緩衝
金属層５または６のかわりに金属製のメツシユを
緩衝金属層７としたものであり、この緩衝金属層
７は金属中間層３ａ，３ｂにロウ付されている。 In the third embodiment, as shown in FIG. 3, a metal mesh is used as a buffer metal layer 7 instead of each of the buffer metal layers 5 or 6, and this buffer metal layer 7 is a metal intermediate layer 3a, 3b is soldered.
上記各実施例構造によれば、各緩衝金属層５，
６，７は伸縮変形に富んだ形状を有しているの
で、接合後の温度変化に伴つて金属母材に大きな
伸縮力が働いても上記伸縮形状化した緩衝金属層
５，６，７の変形によりその力が吸収されてしま
い、セラミツクス２に影響を及ぼすことがなくな
る。 According to the structure of each of the above embodiments, each buffer metal layer 5,
Since the buffer metal layers 5, 6 and 7 have shapes that are highly elastic and deformable, even if a large expansion and contraction force is applied to the metal base material due to temperature changes after joining, the buffer metal layers 5, 6, and 7 that have been expanded and contracted will not be damaged. The force is absorbed by the deformation and no longer affects the ceramics 2.
なお、上記各実施例構造においては、各緩衝金
属層を金属中間層間に介装する構造としたが、金
属母材−緩衝金属層間には少々の応力が発生して
も材質上支障ないので、金属中間層を介さずに直
接ロウ付してもよい。 In addition, in each of the above embodiment structures, each buffer metal layer was interposed between metal intermediate layers, but even if a small amount of stress occurs between the metal base material and the buffer metal layer, there is no problem due to the material. Direct brazing may be performed without using a metal intermediate layer.
次に、この発明の作用効果を定量的に確認する
ために行なつた実施例を示す。 Next, examples will be shown in order to quantitatively confirm the effects of this invention.
〔実験例 １〕
実施例３の構造において、30mm×60mm、厚み５
mmの鋼板を金属母材１とし、15mm×30mm、厚み５
mmのアルミナ焼結体をセラミツクス２とし、金属
中間層３ａ，３ｂとして15mm×30mm、厚み１mmの
銅板を使い、緩衝金属層７として銅製の30mm×15
mm、厚み１mm、メツシユが200の多孔板（メツシ
ユ状部材）を使用して接合一体化した製品（本発
明品）を作製した。[Experiment Example 1] In the structure of Example 3, 30 mm x 60 mm, thickness 5
mm steel plate as metal base material 1, 15 mm x 30 mm, thickness 5
The ceramic 2 is an alumina sintered body with a diameter of 1.5 mm, a copper plate of 15 mm x 30 mm and a thickness of 1 mm is used as the metal intermediate layers 3a and 3b, and a 30 mm x 15 mm thick copper plate is used as the buffer metal layer 7.
A perforated plate (mesh-like member) with a thickness of 1 mm and a mesh size of 200 was used to produce an integrated bonded product (product of the present invention).
この製品に対し、上記同様の金属母材および被
覆セラミツクスを使い、金属中間層として30mm×
15mm、厚み２mmの銅板を使い、従来の接合構造と
なるように接合一体化し、比較品とした。 For this product, we used the same metal base material and coated ceramics as above, and used a metal intermediate layer of 30 mm x
A comparison product was created using a 15 mm x 2 mm thick copper plate and integrated into a conventional bonded structure.
そして、20℃から100℃／分で500℃まで昇温
し、その後500℃で30分間保持、つづいて100℃／
分で20℃まで降温し、20℃で30分間保持の一続き
を１サイクルとする熱サイクルテストに上記本発
明品および比較品をかけて各々の常温における引
張り剪断強度変化を測定した。その結果、第４図
に示すように本発明品は150回の熱サイクルにか
けた後も強度低下が少なく、本発明の信頼性の高
さを確認することができた。 Then, the temperature was raised from 20°C to 500°C at 100°C/min, then held at 500°C for 30 minutes, and then at 100°C/min.
The above-mentioned products of the present invention and comparative products were subjected to a thermal cycle test in which the temperature was lowered to 20°C in 1 minute and held at 20°C for 30 minutes to measure the change in tensile shear strength at room temperature. As a result, as shown in FIG. 4, the product of the present invention showed little decrease in strength even after being subjected to 150 thermal cycles, confirming the high reliability of the present invention.
以上説明したように、この発明によれば、金属
母材の熱的伸縮や外力に伴う変形力がセラミツク
スにかかるのを減少させ、それによりセラミツク
スにおけるクラツクの発生を減少させ、製品の信
頼性の向上および高寿命化を図つた金属とセラミ
ツクスとの接合製品を得ることができる。
As explained above, according to the present invention, it is possible to reduce the deformation force caused by the thermal expansion and contraction of the metal base material and external force applied to the ceramics, thereby reducing the occurrence of cracks in the ceramics, and improving the reliability of the product. It is possible to obtain a metal-ceramics bonded product that is improved and has a longer service life.
第１図ないし第３図は、順次この発明の第１な
いし第３の実施例を示すもので、各々この発明の
接合部材を示す断面図、第４図は本発明品と比較
品とを熱サイクルにかけて接合強度変化を測定し
た結果を示すグラフ、第５図は従来の接合部材を
示す断面図、第６図は第５図−線視図、第７
図および第８図は従来の他の接合部材を示すもの
で、それぞれ要部の底面図および要部側面図であ
る。
１……金属母材、２……セラミツクス、３ａ，
３ｂ……金属中間層、５，６，７……緩衝金属
層。
1 to 3 sequentially show the first to third embodiments of the present invention, each of which is a sectional view showing a joining member of the present invention, and FIG. A graph showing the results of measuring changes in bonding strength over cycles, FIG. 5 is a cross-sectional view showing a conventional bonding member, FIG. 6 is a perspective view of FIG. 5, and FIG.
FIG. 8 shows another conventional joining member, and is a bottom view and a side view of the main part, respectively. 1...metal base material, 2...ceramics, 3a,
3b... Metal intermediate layer, 5, 6, 7... Buffer metal layer.
Claims (1)
接合一体化されている金属−セラミツクス接合部
材において、 金属中間層の中間または金属中間層と金属との
間に緩衝金属層が介装一体化されていることを特
徴とする金属−セラミツクス接合部材。 ２ 緩衝金属層がメツシユ状、くし歯状、束線状
などの伸縮形状化金属部材からなることを特徴と
する特許請求の範囲第１項に記載の金属−セラミ
ツクス接合部材。[Claims] 1. A metal-ceramic bonding member in which a metal and a ceramic are integrally bonded via a metal intermediate layer, wherein a buffer metal layer is provided between the metal intermediate layer or between the metal intermediate layer and the metal. A metal-ceramics bonding member characterized by an integrated intervening member. 2. The metal-ceramic bonding member according to claim 1, wherein the buffer metal layer is made of an expandable metal member having a mesh shape, a comb shape, a wire bundle shape, or the like.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP29023685A JPS62148124A (en) | 1985-12-23 | 1985-12-23 | Metal-ceramics bonding member |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP29023685A JPS62148124A (en) | 1985-12-23 | 1985-12-23 | Metal-ceramics bonding member |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS62148124A JPS62148124A (en) | 1987-07-02 |
| JPH0468264B2 true JPH0468264B2 (en) | 1992-10-30 |
Family
ID=17753516
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP29023685A Granted JPS62148124A (en) | 1985-12-23 | 1985-12-23 | Metal-ceramics bonding member |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS62148124A (en) |
Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP5532601B2 (en) * | 2008-12-22 | 2014-06-25 | 三菱マテリアル株式会社 | Power module substrate and manufacturing method thereof |
-
1985
- 1985-12-23 JP JP29023685A patent/JPS62148124A/en active Granted
Also Published As
| Publication number | Publication date |
|---|---|
| JPS62148124A (en) | 1987-07-02 |
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| LAPS | Cancellation because of no payment of annual fees |