| 摘要 |
<p>A black ceramic sinter which has extremely low thermal expansion and high rigidity and high specific rigidity at room temperature; and a process for producing the sinter. The sinter is characterized by having a chemical composition which comprises 8.0 to 17.2 wt.% MgO, 22.0 to 38.0 wt.% Al2O3, 49.5 to 65.0 wt% SiO2, 0.1 to 2 wt.% one or more transition elements in terms of oxide amount, and 0 to 2.5 wt.% Li2O and in which the proportions by weight of components satisfy the relationships (SiO2 - 8xLi2O) / MgO ≥ 3.0 and (SiO2 - 8xLi2O) / Al2O3 ≥ 1.2. The process is characterized in that the sinter is produced through sintering conducted in a non-oxidizing gas atmosphere at 1,200 to 1,500°C.</p> |
