等离子体辅助球磨活化Al2O3合成AlN

摘要

利用介质阻挡放电等离子体辅助球磨和普通球磨分别对Al2O3粉末进行活化，研究等离子体辅助球磨活化Al2O3合成AlN的碳热还原反应机制。结果表明：等离子体辅助球磨40 h的Al2O3粉末，在N2气氛中于1400℃下保温4 h可以完成碳热还原反应，全部转化为AlN。经等离子体辅助球磨后，Al2O3的碳热还原反应符合气相反应机制，等离子体辅助球磨活化大大降低Al2O3的后续反应温度，辅助球磨40 h后的Al2O3合成AlN的反应激活能下降到371.5 kJ/mol。等离子体的协同效应促使辅助球磨中Al2O3晶体产生更严重的晶格畸变，这是激活 Al2O3并促进碳热还原反应的一个重要因素。%The synthesis mechanism of AlN by Al2O3powders through carbothermic reduction reaction was investigated, in which the Al2O3powders was activated by plasma assisted ball milling (PM) or by conventional ball milling (CM). The results indicate that Al2O3powders activated by plasma assisted ball milling for 40 h can be converted to AlN totally through carbothermic reduction reaction when annealed at 1400℃ for 4h in N2. It is gas reaction mechanism for the carbothermic reduction reaction of Al2O3powders after plasma assisted ball milling. The subsequent reaction temperature of Al2O3powders is reduced significantly because the reaction activation energy decreases to 371.5 kJ/mol after plasma assisted ball milling for 40 h. A lot of lattice distortions are generated in Al2O3graindue to the cooperation of plasma and ball milling, which is an important factor for promoting the carbothermic reduction reaction of Al2O3powders activated by plasma assisted ball milling.