| In this paper, the ultrasonic vibration during compaction of nano-powders is proposed in order to increase the density and reduce the friction without the increase of compaction pressure. The results showed that the friction between die and powder during compaction process was reduced and the density of the compacted nano powder was improved. The high power ultrasonic vibration system of 6 kW with 12 transducers was designed to form a high density nano powder effectively. The compaction results of nano powder core showed that the density of specimen can be improved about 5~15% at the determined optimal condition. And also, the homogeneously dense, unstrained green compact can be formed. Moreover, using the force equilibrium equation in the compaction process, verification of the improvement of density which is caused by ultrasonic compaction was carried out. |
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