煅烧温度对共沉淀法制备热障涂层用LaMgAl11O19前驱粉末性能的影响  

Effect of temperature of coprecipitation on properties of LMA precursors for thermal barrier coatings

作　　者：刘冬梅 李超[2] LIU Dongmei;LI Chao(Department of Architectural Engineering,Chifeng Polytechnic College,Chifeng 024005,China;Institute of metals,Chinese Academy of Sciences,Shenyang 100162,China)

机构地区：[1]赤峰工业职业技术学院建筑工程系,赤峰024005 [2]中国科学院金属研究所,沈阳100162

出　　处：《粉末冶金材料科学与工程》2020年第1期40-44,共5页Materials Science and Engineering of Powder Metallurgy

基　　金：国网沈阳省科技项目(5212HD170005)

摘　　要：采用共沉淀法制备热障涂层用LaMgAl11O19前驱粉末(沉淀温度80℃,沉淀pH值10.5),测试分析煅烧温度对粉末组织形貌和物相组成的影响。研究结果表明:经过1100℃煅烧,粉体由MgAl2O4,LaAlO3和La2O3相组成,随煅烧温度上升至1500℃,形成了具有单一LaMgAl11O19物相结构。所制备的LaMgAl11O19粉体粒径介于3~5μm,厚度为0.5~1.0μm。伴随煅烧温度上升,Mg1s,O1s,La3d和Al2p的电子结合能出现波动,向高能端发生明显位移。当到达1500℃时,Mg,La和Al的电子结合能均增大。在XPS谱图上形成O1s,La3d,Mg2p和Al2p主电子峰,Mg,La和Al被氧化。在LaMgAl11O19晶体内形成了互相交错结构的层状组织,表现为明显的各向异性特征。当煅烧温度上升到1300℃时,La2O3键数量逐渐减小。LaMgAl11O19 precursor powder for thermal barrier coating was prepared by co-precipitation method(precipitation temperature 80℃,precipitation pH value 10.5).The influence of calcining temperature on its microstructure,half-peak full width and spectral strength was tested and analyzed.The results showed that the powder has MgAl2O4,LaAlO3 and La2O3 three phases after calcining at 1100℃.As the calcining temperature rise to 1500℃,the LaMgAl11O19 phase is abtained.The particle size of LaMgAl11O19 is between 3 and 5μm and its thickness is 0.5 to 1.0μm.When the calcination temperature continues to rise,the electron binding energy of Mg1s,O1s,La3d and Al2p fluctuates and shifts significantly towards the high-energy end.At 1500℃,the electron binding energies of Mg,La and Al all increased.The main electron peaks of O1s,La3d,Mg2p and Al2p were formed on the XPS spectrogram,and Mg,La and Al were oxidized.LaMgAl11O19 crystal has formed a layered structure with interlaced structure,which is obviously anisotropic.As the calcination temperature rises to 1300℃,the number of La2O3 bonds gradually decreases.

关 键 词：共沉淀 前驱粉末 LaMgAl11O19 微观组织 谱强 

分 类 号：TG174[金属学及工艺—金属表面处理]