摘要 |
<p>A molten magnesia is air quenched to provide a very large proportion of solid free flowing spheres of fused magnesia, a large percentage of which are smaller than about 35 Tyler mesh, which may be used directly in electrical resistor units without the necessity of crushing and calcining while the larger sized spheres may be crushed if desired and can be used with the uncrushed spheres without being calcined. The method may employ sea water magnesite or any other source of raw material having a high magnesia content that is cheap and readily available, the product being improved and more easily fused by the addition of small amounts of alumina, silica and calcia to the magnesite as it is being fed to the fusion furnace.</p> |