惰气熔融－热导法测定烧结氮化硅中氮

摘要

The nitrogen and oxygen in sintered block Si3N4 can not r elease so completely as the powder sample at the same heating and extracting condition. That is caused by the dynamic diffrence between the block and the powder. If the suitable bath is applied to heating and extracting procedure, the extracting ratio can be increased. Fe bath or Cu bath can improve the extraction, but the extracting time is still too long. The designed 5-element bath results in not only higher extracting ratio but also the best analysis time. The final result of nitrogen is in good agreement with that of determined by chemical analysis. The nitrogen in the block Si3N4 can be determined accurately by inert gas fusion thermal conductivity method combined with 5-element bath. The determination of oxygen in the block sample is also discussed.%粉末压型烧结氮化硅样中氮和氧难以完全释放，其主要原因为烧 结氮化硅样与粉末氮化硅样释放动力学条件不同。熔融提气过程中选用适当的 浴料，可以提高氮氧的释放提取率。单元铁浴和铜浴可改善氮的释放情况，但 分析时间长而拖尾。自行配制的五元浴不仅氮的释放提取率高，而且分析时间 适中；其最终测试结果与化学法测定结果一致。惰气熔融法结合五元浴能够准 确测定烧结氮化硅中氮。本文还对烧结氮化硅样中氧的联测结果进行了讨论。