1996 Fiscal Year Final Research Report Summary
BASIC PROPERTIES OF WHISKER CRYSTALS UNDER TENSION
| Project/Area Number |
07650022
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| Research Category |
Grant-in-Aid for Scientific Research (C)
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| Allocation Type | Single-year Grants |
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| Section | 一般 |
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| Research Field |
Applied materials science/Crystal engineering
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| Research Institution | Science University of Tokyo |
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Principal Investigator |
KISHI Kiyoshi Science University of Tokyo, Assistant Professor, 理学部, 助教授 (90087354)
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| Project Period (FY) |
1997 – 1998
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| Keywords | Whiskers / Tensile Strength / Crystal Growth / Surface Structure / Thin Film / Interface Structure / Surface Tension / Reinforced Materials |
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| Research Abstract |
1. Spiral (or helical) copper whiskers am nearly perfect and show high ultimate tensile strength. These properties are the same as of straight whiskers, but the stress-strain curves are different. Spiral whiskers show no easy-glide region. After the first elastic region, the curve shows gradually out of linear. In this new region many very small but strongly deformed areas periodically occur. Then the deformed areas grow due to the increase in tension but whiskers still keep the high strength 2. Our mass-produced whiskers also show high ultimate tensile strength. 3. A strain-dependent multi-purpose tensile tester for small specimen is built and employed. A new concept of tensile- measurement instruments for nanometric size specimen is also postulated, 4. For both CVD metal whiskers and whiskers of water-soluble materials, a new growth mechanism of whisker crystals under surface tension is described together with computer-simulation. In the present process, the material is supplied via a surface liquid layer such as charges-halide melt or water solution. 5. Two new process of whisker fabrication-growth of water-soluble whiskers with foreign particles aiding the action of surface tension and VLS growth of ITO whiskers under electron shower- are described. 6. AFM observation shows thin {111} film of the charge halide covers the surface of CVD-grown copper whiskers with either epitaxial or CSL low-energy relationships possessing interface tension. 7. According to MD simulation, the {111} halide film already presence between the surface of growing copper whiskers and the top layer of halide-melt and changes the morphology of whiskers.
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Research Products
(8 results)
