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采用自蔓延高温合成工艺，在２０ ～１００ ＭＰａ 高压氮气条件下， 获得氮化完全、致密度接近８０ ％ 的ＡｌＮ 陶瓷。研究了稀释剂含量、氮气压力、毛坯初始空隙率等初始条件对产物转化率和致密度的影响。结果显示， 适量的稀释剂可获得高转化率和相对致密的ＡｌＮ 陶瓷， 稀释剂含量低于４０ ％ 时，由于熔融Ａｌ 团聚， 氮气渗透困难， 反应不完全， 且产物分层； 超过６０ ％ 时， 自蔓延反应不能进行。随着氮气压力增加， 反应转化率提高， 加上气相等静压作用， 有利于提高产物的致密度。当毛坯相对密度ρ０ ＝ ０ ．５９ 时， 可使产物获得较高的致密度， 过大或过小的毛坯相对密度都不利于产物致密度的提高。
The self-propagating high-temperature synthesis process was used to obtain AlN ceramics with complete nitridation and near 80% density under 20-100 MPa high-pressure nitrogen. The effects of initial conditions such as diluent, nitrogen pressure and initial voidage on product conversion and density were studied. The results showed that an appropriate amount of diluent could obtain high conversion and relatively dense AlN ceramics. When the content of diluent was less than 40%, the molten Al was agglomerated, the nitrogen permeation was difficult, the reaction was incomplete, and the products were stratified; when more than 60% , Self-propagating reaction can not be carried out. With the increase of nitrogen pressure, the reaction conversion rate increases, together with the gas isostatic pressing, is conducive to improving the product density. When the blank relative density ρ0 = 0. 59, the product can obtain a higher density, too large or too small relative density of the blank is not conducive to product density increase.