Korean Journal of Materials Research, Vol.27, No.5, 237-241, May, 2017
금속 Ca증기에 의한 고체 Nd 금속의 탈산
Deoxidation of Solid Nd Metal by the Metal Calcium Vapour
As a basic study for the removal of oxygen in solid Nd metal by metal Ca vapour, by using the thermodynamic data such as ΔG-T diagrams and Nd-O and Nd-Ca equilibrium diagrams, the amount of residual oxygen in solid Nd metal formed based on deoxidation reaction by Ca vapour, instead of by direct contact of solid Nd metal and Ca solution, was determined. Deoxidation experiments were carried out for solid Nd metal in a temperature range of 890~970 °C for 1h to 4h and content of addition Ca of 0.6~1.8 g (5~15 wt% of solid Nd metal). As a result, it was found that as deoxidation temperature increased, dissolved oxygen decreased. Especially, it was observed that a small amount of N -Ca alloy liquid was formed on the surface of the solid Nd metal sample deoxidized at 970 °C for approximately 1 hour. Also,it was found that if the content of addition Ca was 1.8 g (15 wt% of solid Nd metal) the amount of produced Nd-Ca alloy increased slightly. However, for the Nd sample with which the deoxidation reaction was performed at 930 °C for 4h with content of addition of Ca of 1.5 g (13 wt% of Nd metal), the residual oxygen was found to decreased to 12.00 ppm.
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