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钕钐对锆酸镧陶瓷粉性能的影响

时间:2018-04-11 14:21来源:毕业论文
通过甘氨酸燃烧法制备锆酸镧陶瓷粉,研究了反应时间、反应温度、甘氨酸用量对锆酸镧陶瓷粉性能的影响,以及探讨了钕部分取代镧对产物性能的影响,实验最后通过XRD、EDS和SEM对产

摘要:本文通过甘氨酸燃烧法制备锆酸镧陶瓷粉,研究了反应时间、反应温度、甘氨酸用量对锆酸镧陶瓷粉性能的影响,以及探讨了钕部分取代镧对产物性能的影响,实验最后通过XRD、EDS和SEM对产品进行表征。从X衍射图分析可知,当温度为750度时,产物特征衍射峰强度高,峰型尖锐,衍射峰半高宽较窄,说明产物的晶体结构比较完整,结晶性比较好;随着反应时间的延长,锆酸镧陶瓷粉的晶体平均粒径增大,结晶度增加,特征衍射峰强度增强,衍射峰的半高宽变窄,可知晶型越来越好;当Gly/M即甘氨酸摩尔量比上金属离子的摩尔总量(La3+和Zr4+)为2:1时,锆酸镧的特征衍射峰十分明显,从出峰情况可以看出此时产物的晶体结构完整,已合成出锆酸镧纳米晶;钕掺杂制备分子式为(LaxNdy)2Zr2O7的产物,当y为0、0.3、0.4时,随着钕元素含量的增加,晶体的平均粒径在减小,产物的聚合度在下降。从EDS图像分析可知,锆酸钐的原子比(Zr、Sm、O)接近2:2:7,而锆酸镧的原子比(La、Zr、O)则为2:3.4:8.4,与理论结果相差较大,可能是由于仪器误差造成的。从SEM图像分析可知,锆酸钐的致密性低,比较松散;而锆酸镧晶体表面有很多细孔,且团聚现象比较明显。20912
毕业论文关键词:热障涂层;陶瓷;涂层性能;锆酸盐
Neodymium and samarium's effect on the properties of lanthanum zirconate ceramics powder
Abstract :In this paper, the method of glycine combustion is used to prepare lanthanum zirconate ceramics, It is studied on the different effects on anthanum zirconate ceramics powder caused by the difference of reaction time, reaction temperature and dosage of glycine ,Apart from this ,this paper also discusses the effect on the product properties caused by neodymium replace part of the lanthanum. In the last ,the products are characterized by XRD, EDS and SEM. The research results show that when the temperature is 750 degrees, the product shows all the characteristics of diffraction peak, and the diffraction peak intensity is high and sharp, the crystalline structure of the product is complete; As the extension of reaction time, crystal average particle size of lanthanum zirconate ceramics powder increases, the crystallinity increases, the characteristics of the diffraction peak intensity is enhanced, and a half high width of the diffraction peak Narrows, so the crystal structure is more perfect; When Gly/M is 2:1, the characteristic diffraction peak of lanthanum zirconate is very clear,  crystal structure is complete, thus zirconate nanocrystals of lanthanum have been made; Neodymium is doped with the preparation of the product of the formula for the (LaxNdy)2 Zr2O7, when y is 0, 0.3, 0.4, with the increase of content of neodymium, average particle size in the crystal decreases, and the degree of polymerization of product is falling. For the SEM image analysis, atomic ratio of zirconate samarium (Zr, Sm, O) is close to 2:2:7, and atomic ratio of lanthanum zirconate (La, Zr, O) is 2:3.4:8.4, is a little far different of the theoretical results, may be it is caused by the instrument error. EDS image analysis shows that the density of zirconate samarium is low, relatively loose; And the crystal surface of lanthanum zirconate has many pores, and reunion phenomenon is more obvious.
Keywords: thermal barrier coatings ; ceramic ; coatiang performance;zirconate
 
目录
1前言    1
1.1热障涂层陶瓷材料    1
1.1.1传统热障涂层陶瓷材料    1
1.1.2新型热障涂层材料    1
1.2稀土元素    3
1.3溶盐法    3
1.4固相反应法    4
1.5溶胶-凝胶技术    5
1.6共沉淀法    6
1.7低温燃烧合成法    6 钕钐对锆酸镧陶瓷粉性能的影响:http://www.751com.cn/huaxue/lunwen_12873.html
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