摘要：本文以氧化锆和氧化镧为原料，氯化钠和氯化钾为助熔剂，采用熔盐法制备锆酸镧陶瓷粉。研究了不同研磨时间、熔盐比、反应时间、反应温度、熔盐种类对锆酸镧粉体纯度和相结构的影响。用扫描电镜（SEM）、电子能谱仪（EDS）对粉体进行表征。由X衍射图分析可知，随研磨时间增加，反应进行程度增大，生成的锆酸镧陶瓷粉越纯净，晶型结构越完整，研磨时间为3-4h比较好；盐的熔体在反应中起到溶剂和反应介质的作用，并不改变反应进行程度，熔盐比对产物的纯度和相结构影响较小；随反应时间的增加，生成产物的量增多，当反应时间接近7h时，反应近乎完全，得到较纯净的反应产物，晶型完美；反应温度的升高有利于产物的形成，当温度接近1200℃左右时，反应近乎完全，得到的锆酸镧陶瓷粉较纯，晶型结构完整；用氯化钠作反应助熔剂比硫酸钠好，制得的锆酸镧陶瓷粉更纯净，晶体结构更完整。由EDS图像分析可知，产物中La、Zr、O三种元素的含量比为2:2.78:8.73，与理论结果2:2:7相差较大，可能是由于仪器误差造成的。由SEM分析锆酸镧的晶体形貌可知，锆酸镧晶体颗粒为片状，晶体颗粒排布布紧密，存在着较明显的团聚现象，聚团块与块间有空隙。22509
毕业论文关键词：熔盐法、锆酸镧陶瓷粉体、晶型
Preparation of lanthanum zirconate ceramic powder by Molten Salts method
Abstract：In this paper, zirconium oxide and lanthanum oxide as raw material , sodium chloride and potassium chloride as a flux , using molten salt prepared lanthanum zirconate ceramic powder. The effects of different grinding time , molten salt , reaction time, reaction temperature , molten salt type on lanthanum zirconate powder purity and phase structure . Scanning electron microscopy (SEM), electron spectroscopy (EDS) for powder characterization. By the X-ray diffraction diagram analysis , with the grinding time increases , the degree of reaction increases, generated more pure lanthanum zirconate ceramic powder , the more complete the crystal structure , the grinding time is 3-4h better ; salt melt reaction act as a solvent and reaction medium , the reaction does not change the level of the molten salt has no effect on the ratio of product purity and phase structure ; with increasing reaction time, the increased amount of the resulting product , when the reaction time is close to 7h, the reaction almost completely to obtain a purer reaction product , crystalline perfection ; reaction temperature favors the formation of the product , when the temperature is close to about 1200 ℃, nearly complete reaction , the resulting lanthanum zirconate ceramic powder and pure full crystal structure ; using sodium chloride as a reaction better than the flux , the resulting lanthanum zirconate ceramic powder is more pure , more complete crystal structure . EDS analysis of the images shows that the product La, Zr, O content ratio of 2:2.78:8.73 three elements , with the theoretical results 2:2:7 large difference may be due to an error caused by the instrument . SEM analysis of the crystal morphology known lanthanum zirconate , lanthanum zirconate crystal particles flake, crystalline particles row boob closely , there are obvious agglomeration between clumps together with the block there is a gap .
Keywords: molten salt method;lanthanum zirconate ceramic powder;crystalline
目 录
1 引言 1
1.1 热障涂层的相关介绍 1
1.2 锆酸镧陶瓷粉 1
1.3 陶瓷粉末的制备 2
1.3.1 固相反应法 2
1.3.2 溶胶凝胶法 2
1.3.3 化学共沉淀法 3 熔盐法制备锆酸镧陶瓷粉的研究:http://www.751com.cn/huaxue/lunwen_15178.html