摘要 |
<p>The high-purity, heat-resistant oxynitride glass can be produced by subjecting a fine silica powder block to a nitriding treatment by heating it while keeping it in contact with an ammonia-containing gas in a reducing environment, which is achieved by at least one of the following means: (a) embedding the fine silica powder block in carbon powder, (b) placing the fine silica powder block in a carbon pipe or container, and (c) introducing a reducing gas, and simultaneously or subsequently sintering it.</p> |