| 摘要 |
<p>A tar-impregnated burned basic refractory brick is prepared from a grain consisting of 88-96% MgO, 1-3% of at least one reducible metal oxide which does not react with the other components of the brick to form melts below 2700 DEG F., e.g. iron oxide, manganese oxide, chromic oxide or titania, the CaO : SiO2 ratio of the grain being at least 2 : 1, the grain containing up to 1% of other impurities and the tar impregnation being throughout the internal voids and over the external surfaces of the brick. After burning the reducible oxide may be in the form of metal or a suboxide.</p> |
