摘要
采用等温热重法,测试了NiFe2O4基金属陶瓷在1000℃时的抗氧化性能,研究了材料相对密度、金属相成分及含量对其抗氧化性能的影响,探讨了金属陶瓷氧化过程的动力学。研究结果表明:当NiFe2O4基金属陶瓷的氧化层厚度增长到一定程度后,随时间的延长其厚度变化渐趋缓慢;当金属相含量在5%～20%范围时,材料的高温抗氧化性能主要受其相对密度影响,与金属相成分及含量无关,提高金属陶瓷的致密度有利于提高其抗氧化性能,当相对密度为95%时,在1000℃氧化600min后其氧化层厚度小于3μm;控制金属陶瓷的致密度和高温下的氧化时间,能有效地控制金属陶瓷的氧化层厚度;金属陶瓷在1000℃时的氧化过程动力学特征与金属相的氧化过程动力学特征相似。
The anti-oxygen performance of NiFe_2O_4 based cermets at 1 000 ℃ was studied with an isothermal heat-weight method, the influence of relativity density, composition and content of metal on its anti-oxygen performance was investigated and the oxidation kinetics was also discussed. The results reveal that the change of oxide thickness of cermets with time prolonging becomes slow when the thickness reaches some degree. When the content of metal is in the range of 5%20%, the influence on anti-oxygen performance of cermets at high temperature is not mainly due to the composition and content of metal but its relativity density, increasing relativity density is beneficial to improve its anti-oxygen performance and the oxide thickness is thinner than 3 μm after 600 min at (1 000 ℃) when its relativity density is above 95%. Controlling relativity density of cermets and oxide time at high temperature can effectively control oxide thickness. The dynamic process of oxidization for NiFe_2O_4 based cermets is similar with that of metals at 1 000 ℃.
出处
《中南大学学报（自然科学版）》
EI
CAS
CSCD
北大核心
2004年第6期902-906,共5页
Journal of Central South University:Science and Technology
基金
国家"863"计划项目(2001AA335013)
湖南省自然科学基金资助项目(03JJY3080)
关键词
铝电解
NiFe2O4基金属陶瓷
抗氧化性
相对密度
aluminium electrolysis
nickel ferrite based cermets
anti-oxygen performance
relativity density
