| Project/Area Number |
63550515
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| Research Category |
Grant-in-Aid for General Scientific Research (C)
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| Allocation Type | Single-year Grants |
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| Research Field |
金属材料(含表面処理・腐食防食)
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| Research Institution | Hokkaido University |
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Principal Investigator |
NARITA Toshio Fac. of Engineering, Hokkaido University, Associate Professor, 工学部, 助教授 (60001252)
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| Project Period (FY) |
1988 – 1989
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| Project Status |
Completed (Fiscal Year 1989)
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| Budget Amount *help |
¥2,000,000 (Direct Cost: ¥2,000,000)
Fiscal Year 1989: ¥500,000 (Direct Cost: ¥500,000)
Fiscal Year 1988: ¥1,500,000 (Direct Cost: ¥1,500,000)
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| Keywords | Ceramic / metal bonding / Silicon nitride ceramic / Reactive metal solder / Four-point bending strength / Thermal residual stress / Ultra-sonic microscope / Surface acoustic wave / Heat treatment / 窒化ケイ素セラミックス / ジルコニアセラミックス / 窒化珪素セラミックス / セラミックス / 金属接合体 / 拡散処理 / 接合層の改質 / 接合体の強度 / セラミックスと金属の反応 |
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| Research Abstract |
To produce ceramic/metal bondings with heat resistance and high fracture strength, five items were experimentally investigated and could be summarized as follows: From screening tests of solder and interlayer materials for depression of thermal residual stress, triplex layer structures of Ti(1.5um)- Cu(20um)-Ni(a part of nickel interlayer) and of Ni(t)-W(t=1mm)-Ni(t=1mm) were finally selected as candidate solder and interlayer materials. It was found that a maximum fracture strength of 240MPa was obtained at room temperature when a thickness of nickel interlayer is about 1.3mm. This fracture strength increased with increase in test temperatures and reached about 290MPa at 400ﾟC and then decreased gradually, but it is still higher than 180MPa at 800ﾟC. The bonding was heated at 1000ﾟC up to 100hr in vacuum and showed little change in fracture strength and raction bonding layer structures. In oxidizing atmospheres as in air it was found that a high fracture strength of this bonding was k
… More
ept up to 600ﾟC and above this critical temperature a fracture strength decreased rapidly due to the selective oxidation of the tungsten layer. Instead of tungsten an interlayer with anti-oxidation property has to be developed and is now under progress.
A ultra-sound microscope was used for non-destructive evaluation of thermal residual stress developed on the ceramic surface when it was joined to metals. The principle of this method is to measure velocity of leaky surface acoustic wave, which changes dependent on stress conditions, namely, the velocity decreases with tension stress and the reverse case is for compressive stress. This novel technique enables us to measure stress distribution in the vicinity of ceramic/metal bonding interface. The results obtained are reasonable, except several new findings which is unexplainable using existing knowledges. In order to understand these new results further theoretical and experimental investigations should be required and are under progress in our laboratory. Less
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