摘要
为了提高暖通冷凝器用LaMgAl11O19热障涂层的稳定性,在温度80℃,p H值10.5条件下采用沉淀法制备LaMgAl11O19粉末,并在马弗炉内以不同温度(1100~1500℃)烧结6 h,通过X射线衍射仪(XPS)、透射电镜(TEM)、扫描电镜(SEM)测试分析烧结温度对其组织形貌、半峰全宽和谱强的影响。结果表明:随着烧结温度的升高,形成了更强的LaMgAl11O19衍射峰,生成具有五角结构的LaMgAl11O19粉末,粒径尺寸3~5μm。XPS表征LaMgAl11O19粉体显示形成了Al2p、La3d、O1s、Mg2p电子衍射峰,Mg、La、Al 3种元素都发生了氧化。提高烧结温度后,各元素发生电子结合能波动变化。初始LaMgAl11O19前驱体粉末逐渐转变为单一结构,MgAl2O4的半峰宽明显增大。以低于1300℃的温度烧结基本都是生成配位键化合物La2O3,获得尖晶石组织;随着烧结温度高于1300℃后,生成大量La-Al-O组织,得到对称分布的尖晶石层。
In order to improve the stability of LaMgAl11O19 thermal barrier coating for heating ventilation and air conditioning(HVAC)condenser,LaMgAl11O19 powder was prepared by the precipitation method at the precipitation temperature of 80℃and p H value of 10.5 as well as post-sintered treatment by muffle furnace at 1100-1500℃.Subsequently,the influence of the preparation temperature on the microstructure,half-peak width and spectrum strength of LaMgAl11O19 powder was analyzed by X-ray diffraction(XRD),X-ray photoelectron spectroscopy(XPS),transmission electron microscope(TEM)and scanning electron microscope(SEM).Results showed that with the increase of sintering temperature,the characteristic diffraction peaks of LaMgAl11O19 became stronger,which revealed the formation of LaMgAl11O19 powders with pentagon structure and 3-5μm of particle size.XPS characterization displayed that Al2p,La3d,O1 s,Mg2p electron diffraction peaks were observed from LaMgAl11O19 powders,and Mg,La and Al elements appeared oxidation state.As the sintering temperature increased,the binding energy of every element fluctuated.Meanwhile,the original LaMgAl11O19 powders changed gradually into single structure,and the half-peak width of MgAl2O4 increased obviously.When the sintering temperature was below 1300℃,the coordinate bond compounds La2O3 with spinel structure generated.When the temperature increased to higher than 1300℃,lots of La-Al-O tissues were generated,and a symmetrically distributed spinel layer was obtained.
作者
胡颂
李梦启
HU Song;LI Meng-qi(Jiangxi General Institute of Architectural Design and Research,Nanchang 330046,China;Key Laboratory of Intelligent Manufacturing of Efficient Power System,Shaoyang 422000,China)
出处
《材料保护》
CAS
CSCD
北大核心
2020年第5期79-82,共4页
Materials Protection
