| 摘要 |
<p>New ceramic material and process for its fabrication, applicable to the fabrication of tiles and the like, from slate and residues thereof, comprising the sieving of dry powder of slate to less than 100 microns and having a water content lower than 5 %, the homogenization and conditioning of the same in order to introduce said sieved slate powder into a sealed vacuum-closed elastic mold, compacting the mold with the powder to pressures of approximately 170 MPa; the compacted unit is then extracted from the mold and machined into rectangular test pieces, rectified if required with Sic or abrasive materials of similar hardeness; it is then placed inside a sintering oven where it is heated during 30 minutes at a rate of 5 °C/min., and at a temperature from about 1150 °C to 1175 °C; it is subsequently cooled at the same rate as it was heated but in the reverse way, minus 5 °C/min., while the atmosphere of air is maintained at any time; the mold may also be a floating matrix lubricated with zinc stearate; the dry powder may subsequently be compacted by means of a press to a final pressure ranging from 100 MPa and 300 MPa; the compacted product is removed from the matrix and introduced in the sintering oven with similar times and rates of heating and cooling.</p> |
