(1. 集美大学 轮机工程学院 福建省船舶与海洋工程重点实验室,厦门 361021;
2. 大连理工大学 材料改性教育部重点实验室,大连 116024;
3. Department of Materials Science and Engineering, North Carolina State University, Raleigh 27695, USA)
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。
关键字: Al2O3;等离子体辅助球磨;活化;碳热还原反应;AlN
(1. Fujian Provincial Key Laboratory of Naval Architecture and Ocean Engineering,
Institute of Marine Engineering, Jimei University, Xiamen 361021, China;
2. Key Laboratory of Materials Modification, Ministry of Education,
Dalian University of Technology, Dalian 116024, China;
3. Department of Materials Science and Engineering, North Carolina State University, Raleigh 27695, USA)
Abstract:The synthesis mechanism of AlN by Al2O3 powders through carbothermic reduction reaction was investigated, in which the Al2O3 powders was activated by plasma assisted ball milling (PM) or by conventional ball milling (CM). The results indicate that Al2O3 powders 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 Al2O3 powders after plasma assisted ball milling. The subsequent reaction temperature of Al2O3 powders 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 Al2O3 grain due to the cooperation of plasma and ball milling, which is an important factor for promoting the carbothermic reduction reaction of Al2O3 powders activated by plasma assisted ball milling.
Key words: Al2O3; plasma assisted ball milling; activation; carbothermic reduction reaction; AlN