Preparation Of Cu Nano-powder And Characterization Of Nano-bulk Materials

Pure metallic Cu nano-particles were prepared successfully by method of hydrogenarc discharging plasma in this experiment. The effects of current, pressure and the ratio ofhydrogen to argon on the grain size and production have been studied. It was found thatthe main factor that affects the production is current. Higher current leads to higherproduction. The leading factor that improves the particle size is the gas pressure. Highergas pressure leads to larger grain size. The optimized experiment conditions for pure Cunano-particles are determined to be a current of300A,1:1ratio of hydrogen to argon andtotal gas pressure of0.06MPa.The phase, morphology and mechanical property of nano-particles have beeninvestigated. The Cu nano-particles have a single face-centered cubic phase. The averageparticle size of Cu nanopowders calculated by Scherrer formula to be50.56nm. The smallaverage particle size results in the widen of diffraction peak. Most of the nanopowders areround, tiny, homogeneous and smooth. The nanopowders are linked with each other like achain.Nano-bulk was obtained by Spark Plasma Sintering in different temperature andpressure. In order to study the solidification behavior of metallic Cu nano-particles. Inorder to get excellent mechanical property, the current and pressure were adjusted to findthe optimal process conditions. It is found that the maximal rigidity of sample is216.83Hvwhen the temperature is400℃. The maximal tensile strength is476.45MPa whentemperature is500℃and pressure is50MPa. The maximal density of the sample is7.74g/cm~3when temperature is600℃and pressure is50MPa.FESEM fracture configuration show that higher temperature bring out larger size ofthe dimple, at the same time, some cracks are founded in the fracture, which is likely to bethe main reason of low plasticity.