为了降低合成成本,以低能耗、低成本的天然锆英石、工业氧化铝和焦炭为原料,采用碳热还原氮化法合成了ZrN-SiAION复相材料.根据反应方程式3Al2O3+ 6ZrSiO4+ 27C+ 8N2=6ZrN+ 2Si3Al3O3N5+27CO设计锆英石和工业氧化铝的原料配比,改变还原剂焦炭的配入质量分数(分别为理论用量、过量5％、过量10％、过量20％),经球磨混合、成型、干燥后,在流动氮气中分别于1 500、1 550、1 600℃保温4h合成,自然冷却后分析合成产物的相组成和显微结构.结果表明:1)在合成温度为1 500℃时,配碳量的增加有助于ZrN的生成；2)在合成温度为1 550℃时,配炭量过量20％的试样中有15R型的多型体SiAlON(即SiAl4 O2 N4)生成；3)在合成温度为1600℃时,配碳量为理论量和过量5％的试样中的多型体SiAlON为15R型,而配碳过量10％和20％的试样中的多型体SiAlON则主要为12H型(即SiAl5O2N5).%Natural zircon,alumina and carbon coke were used as starting materials for the preparation of ZrN-SiAION composite by carbonthermal reduction nitridation. The mass ratio of zircon and industrial alumina was designed according to equation 3AI2O3 +6ZrSiO4 +27C +8N2 = 6ZrN +2Si3AI3O3N, +27CO. The additions of carbon coke were stoichiometric amount,excess 5 mass%,excess 10 mass% and excess 20 mass% .respectively. After ball-milling,molding,drying and firing at 1 500,1 550 and 1 600 °C for 4 h under flowing nitrogen followed by natural cooling down to room temperature,respectively,the phase compositions and micro-structure of the synthetic products were investigated. The results show that: (1) increasing coke content is beneficial to the formation of ZrN at 1 500 °C; (2) when the firing temperature is 1 550°C,there is 15R-SiAI4O2N4(SiAI4O2N,) in the products with excess 20 mass% carbon coke addition;(3)when the firing temperature is 1 600 "C,there is 15R-SiAI4O2N4 in the products with stoichiometric or excess 5 mass% carbon coke addition and there is 12H-SiAI4O2N4(SiAl5O2N5) in the products with excess 10 mass% or excess 20 mass% carbon coke addition.
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