为降低碳热还原氮化法制备AlN粉体的反应温度,减小粉体粒径、缩短反应时间,以勃母石(γ-AlOOH)为铝源、蔗糖为碳源,采用碳热还原氮化法在不同温度下制备了AlN超细粉体,用XRD、TEM等方法分析了所制备粉体的物相组成与形貌.结果表明:在1 480 ℃、流通氮气氛中保温1 h可制备出平均粒径为350 nm的AlN粉体,大幅度降低了反应温度,缩短了反应时间;在高温下,γ-AlOOH分解成Al2O3,部分Al2O3被碳还原成气态铝和铝的低价氧化物(Al2O,AlO),它们与氮气直接反应生成AlN和中间相AlON,随后中间相AlON也发生反应生成AlN.

In order to reduce the reaction temperature and powder size of AlN synthesized by carbothermal reduction and nitridation method and shorten the reaction time,AlN ultrafine powders were prepared at different temperatures with boehmite (γ-AlOOH) as aluminum resource and sucrose (C12H22O11) as carbon resource.Phase compositions and appearance of the prepared powders were analyzed by XRD and SEM.The results show that AlN powders with average grain size of 350 nm could be obtained with holding time of 1 h at 1 480 ℃ in flowing N2 atmosphere,which dramatically reduced the reaction temperature and shortened the reaction time.At high temperature,γ-AlOOH decomposed into Al2O3,and then partial Al2O3 was reduced by carbon to aluminum vapor,Al2O and AlO which could react with nitrogen to form AlN and AlON intermediate phase.Then AlON gradually transformed to AlN by further reaction with carbon or CO.