sintered corundum

例句：

1. 1. Theengineer used a special machine to sinter the corundum.
   工程师使用一种特殊的机器来烧结刚玉。
2. 2. Thesintered corundum was used in makinghigh-quality ceramics.
   烧结的刚玉用于制造高质量的陶瓷。
3. 3. Thesintered corundum was usedas an abrasive material forpolishing tools.
   烧结的刚玉用作抛光工具的磨料。