摘要
以氯氧化锆、硝酸钙和氨水为原料,并掺杂摩尔数分数为5％的硝酸钙与共沸蒸馏分散相结合,采用化学共沉淀法制备ZrO_2-CaO纳米粉末。DTA分析表明化学共沉淀前驱体在温度为593.81℃和1234.56℃时发生相转变。经在400,600,1100和1300℃煅烧1 h后所得粉末,用TEM及BET测定其粒子尺寸,用XRD和Raman光谱分析其相结构,讨论了氧化钙的存在及粒径等因素对氧化锆四方相稳定的影响。结果显示:前驱体经600℃和1 100℃煅烧后,可在室温下分别得到平均粒径为9.8 nm和43.7 nm的四方氧化锆纳米粉末。在掺杂摩尔数分数为5％的硝酸钙的ZrO_2-CaO纳米粉末中,四方相的稳定区在600～1 100℃,1 234.5℃为四方相向单斜相转变的临界温度。
Nanometer-sized powder of ZrO_2-CaO was prepared by chemical co-precipitation method under the doping of nitrate of lime and azeotropic distillation, with zirconium oxychloride and amonium as the raw materials. Phase transformation under 593.81℃ and 1 234.56℃ is observed in the chemical co-precipitation precusor through DTA analysis. Phase structure was analysed through XRD and Raman spectrum. The particle size of tetragonal zirconium oxide powder is equal to 9.8 nm and 43.7 nm under the calcination of 600℃ and 1 100℃ respectively which was tested by the TEM and BET analysis. The influence of the nitrate of lime's doping and the zirconium oxide's partical size to the stability of retragonal zirconium oxide was discussed in this paper. The results show that the stable region of tetragonal phase is from 593.81℃ to 1 234.56℃ and the critical temperature of the phase transformation from tetragonal phase to monoclinic phase is 1 234.56℃ in the nanometer-sized ZrO_2-CaO.
出处
《粉末冶金材料科学与工程》
EI
2002年第4期265-270,共6页
Materials Science and Engineering of Powder Metallurgy
基金
国家"863"计划项目(2001AA218011)
关键词
共沉淀法
ZrO2-CaO
纳米粉末
相转变
chemical co-precipitation method
ZrO_2-CaO
nanometer-sized powder
phase transformation
