| Project/Area Number |
04650630
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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 |
金属加工(含鋳造)
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| Research Institution | Nagoya Institute of Technology |
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Principal Investigator |
OHASHI Teruo Nagoya Institute of Technology, Mater, Scl.Eng., Professor, 工学部, 教授 (70024263)
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| Project Period (FY) |
1992 – 1993
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| Project Status |
Completed (Fiscal Year 1993)
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| Budget Amount *help |
¥1,900,000 (Direct Cost: ¥1,900,000)
Fiscal Year 1993: ¥700,000 (Direct Cost: ¥700,000)
Fiscal Year 1992: ¥1,200,000 (Direct Cost: ¥1,200,000)
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| Keywords | powder metallurgy / Cu-Pb alloy / liquid phase sintering / mechanical grinding / slide bearing / dilatometry / 銅-鉛合金 / 焼結 / メカニカル・アロイング / 銅ー鉛合金 |
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| Research Abstract |
Effect of mechanical grinding (MG) on the sintered structures and sintering characteristics of the Cu-Pb alloys has been investigated by dilatometric measurements and structural observations. It was shown that the structures of the alloys powders which were sufficiently pulverized by a a ball-milling of high energy type were composed from the crystallites the diameter of which was more or less than 50nm. The resultant redistribution of Pb in the copper matrix could be so accepted that the sintered compacts of these powders improved wear resistance. A distinctive dilatometric change was observed during isochronal sintering these MG powders in hydrogen atmosphere. Two peaks were observed in the dilatation curves, the first at 673K, the second at 973K.Sintering proceeded above the second peak temperature with a shrinkage in volume, the amount of which increased with increasing MG time.
Sintering mechanism has been also discussed in viewing the isothermal sintering behaviors of MG powders. During sintering the expansion preceded the shrinkage in the powder compact volume. The copper particles grew according to the cube root of time followed by a shrinkage in volume of the powder compacts. Activation energies for the particle growth were estimated to be 85, 173 and 230kj/mol for the powder compacts of MG time's 0 hr, 6 hr and 20 hr, respectively. It was suggested such a difference in the activation energy is due to the morphology of the copper partices which was affected by MG treatment.
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