Author:
Yokoyama S,Nakano K,Sasano J
Abstract
Abstract
Copper has been levitation-melted in room temperature Ar and N2 gas flows to investigate the evaporation rate and characteristics of condensed particles. The evaporation measured experimentally increased with the increases of the temperature of the levitated Cu, and the gas flow rate. The site, the concentration and temperature at the vapor condensation in the gas film around the levitated Cu was analysed using the temperature distribution and the critical supersaturation concentration of Cu vapor. There was a linear relationship between the calculated and the experimentally obtained evaporation rates. The calculated evaporation rate was larger than the experimentally measured rate. The condensed particles were metallic Cu. When the temperature at the vapor condensation site was lower than the melting point of Cu, the vapor condensed as a solid phase, and the solid particles did not grow with collision-coalescence of the particles. Therefore, the size of them was not influenced by the temperature of levitated Cu and the gas flow rate. When the temperature at the condensation site was higher than the melting point, the size of them was increased by the distance which was the difference in the position at the melting point and the vapor condensation.