| Alumina dispersed copper alloy was manufactured as a material requiring high temperature strength, endurance to thermal fatigue, and good thermal and electrical conductivity. The material was fabricated by mixing, compaction, sintering at hydrogen atmosphere, and hot pressing, where the size of Cu powder was 3∼5㎛ and those of Al₂O₃powder were 3∼5㎛, 0.06 and 0.30㎛. The amount of alumina in the specimen varied from 0.5 to 5 percent. The optimum sintering was obtained at 1,000℃ for 1hr, and micro vickers hardness at room temperature was maximum at Cu-3.0w/o Al₂O₃. Dispersion strengthening effects were found considerable at high temperature. When the amount of alumina in the dispersion strengthened alloy increase more than 3%, the hardness and strength decreased due to coalescence of dispersion, and decrease in density. Cu-3.0 w/o Al₂O₃was discovered to increase the tensile strength by 67% compared with pure Cu. |
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