| 摘要 |
<p>Oxide refractory materials (for example, alumina-zirconia mixtures) can be cast to have an extremely fine crystal structure, by casting a melt of oxide refractory materials onto a non-reactive, non-melting particulate solid cooling media of a material other than that of the oxide refractory material (for example, steel spheres having a size ranging from about 5 to about 60 millimeters). The casting takes place within a solidification chamber having an opening in its lower end, through which the cooling media and solidified oxide refractory melt can be removed. According to one embodiment, the opening in the lower end of the solidification chamber is either temporarily completely blocked by a base, which is periodically removed to allow the recovery of cooling media and solidified oxide refractory melt, or continuously partially blocked by the base, so that the cooling media and solidified oxide refractory melt can be continuously recovered from the solidification chamber. According to another embodiment, no base at all is required, but the continuous discharge of cooling media and solidified oxide refractory melt is controlled by the angle of inclination of the cylinder which constitutes the solidification chamber. The solidified material, when crushed and graded, has exceptional utility as an extremely tough abrasive grain.</p> |
