(1. 中南大学 冶金科学与工程学院, 长沙 410083；
2. 中南大学 粉末冶金国家重点实验室， 长沙 410083)
摘 要: 采用冷压-烧结技术制备了CaO掺杂的10NiO-NiFe2O4复合陶瓷， 研究了CaO掺杂量及烧结温度对10NiO-NiFe2O4复合陶瓷物相组成、 显微结构及致密度的影响。 结果表明：当CaO掺杂量为0～4%（质量分数）时，烧结样品中主要含有NiO和NiFe2O4两种， CaO与10NiO-NiFe2O4陶瓷组分反应并形成低熔点相，且Ca2＋离子固溶到基体组分中， 促进致密化烧结， 降低了烧结温度；当CaO掺杂量为4%时， 过剩的CaO存在于陶瓷颗粒间， 抑制了致密化过程的进行； 于1 200 ℃烧结时， 2%CaO掺杂样品的相对密度最大， 达到98.75%，比未掺杂样品的相对密度提高近24%； 当烧结温度从1 200当升高到1 400 ℃时， CaO掺杂量为0、 0.5%和1.0%的样品相对密度提高20%以上， 但当CaO掺杂量为2%和4%时， 陶瓷样品相对密度反而下降， 且晶粒明显长大。
附件:(2006)08-1355-06
关键字: 10NiO-NiFe2O4复合陶瓷； CaO掺杂； 惰性阳极； 铝电解； 致密化
10NiO-NiFe2O4 composite ceramics
（1. School of Metallurgical Science and Engineering,
Central South University, Changsha 410083, China;
2. State Key Laboratory of Powder Metallurgy,
Central South University, Changsha 410083, China）
Abstract: The CaO doped 10NiO-NiFe2O4 composite ceramics were prepared with the cold isostatic pressing-sintering process, the effects of CaO content and sintering temperature on the phase composition, microstructure and density of 10NiO-NiFe2O4 composite ceramics were studied. The results show that the samples are mainly consisted of NiO and NiFe2O4 when content of CaO is 0-4%(mass fraction), CaO reacts with the component of 10NiO-NiFe2O4 ceramics and forms low melting point phase, and Ca2+ dissolves into the ceramic base, which is important to accelerate the sintering densification and reduce sintering temperature. When sintered at 1 200 ℃, the samples doped with 2% CaO have the maximum relative density(98.75%), which increases about 24% compared with the undoped samples. When the CaO content is 4%, the excessive CaO indwelling between the base ceramic grains restrains the densification of 10NiO-NiFe2O4 composite ceramics. When the sintering temperature rises from 1 200 to 1 400 ℃, the relative density of the samples doped with 0, 0.5% and 1% CaO increase 20%, but the relative densities of the samples doped with 2% and 4% CaO decrease and the grains coarsen obviously.
Key words: 10NiO-NiFe2O4 composite ceramics; CaO doping; inert anode; aluminum electrolysis; densification
