The dissolution behaviors of Dy2O3 in molten CaCl2
The spherical Dy2O3 particles used in CSLM-IIF observation were prepared by grinding sintered particles of Dy2O3 of approximately 1 mm. The diameter of the final spherical Dy2O3 particles is 350-400 pm.
In-situ observations of the dissolution of Dy2O3 in molten CaCl2 were carried out with a resolution of 0.25 pm using the CSLM-IIF equipment. Details of the CSLM technique have been published elsewhere [7-10]. A recrystallized alumina crucible (5 mm diameter and a height of 8 mm) was used in this experiment, and it was placed in a bigger platinum crucible (10 mm diameter and a height of 10 mm) against accidental spillage. The CaCl2 employed in the CSLM experiments was prepared using the above procedures. The pre-melted CaCl2 was loaded into the crucible, heated in ultra-high purity argon (99.999%) in the CSLM up to 1173 K (900 °C) and cooled to form a uniform flat surface. The spherical Dy2O3 particles were placed on the surface of the solid salt. The entire assembly was heated to 1173 K (900 °C) under ultra-high purity argon. The details of this process have been described elsewhere [9, 10].