CAJ | 학술논문

采用电子束物理气相沉积技术(EB-PVD)制备了新型La2(Zr0.7Ce0.3)2O7 (LZ7C3)热障涂层.研究了涂层的组分、显微结构、表面和横截面形貌以及恒温氧化行为.结果表明:涂层中La2O3/ZrO2/CeO2的相对含量偏离了化学计量比,但X 射线衍射(XRD)相结构与靶材非常相似.通过CeO2 掺杂后,LZ7C3体材料的热膨胀系数比La2Zr2O7 (LZ)大;在1100℃恒温氧化890h的条件下,LZ7C3涂层的抗氧化增重性能明显优于传统的Y2O3部分稳定化的ZrO2(8YSZ)涂层.此外,热膨胀不匹配、黏结层氧化和陶瓷涂层内部微观裂纹的出现可能是导致LZ7C3涂层恒温氧化失效的主要原因.
채용전자속물리기상침적기술(EB-PVD)제비료신형La2(Zr0.7Ce0.3)2O7 (LZ7C3)열장도층.연구료도층적조분、현미결구、표면화횡절면형모이급항온양화행위.결과표명:도층중La2O3/ZrO2/CeO2적상대함량편리료화학계량비,단X 사선연사(XRD)상결구여파재비상상사.통과CeO2 참잡후,LZ7C3체재료적열팽창계수비La2Zr2O7 (LZ)대;재1100℃항온양화890h적조건하,LZ7C3도층적항양화증중성능명현우우전통적Y2O3부분은정화적ZrO2(8YSZ)도층.차외,열팽창불필배、점결층양화화도자도층내부미관렬문적출현가능시도치LZ7C3도층항온양화실효적주요원인.
La2(Zr0.7Ce0.3)2O7 (LZ7C3) as a candidate material for thermal barrier coatings (TBCs) was coated by electron beam-physical vapor deposition (EB-PVD). The composition, crystal structure, surface and cross-sectional morphologies and isothermal oxidation behavior of the LZ7C3 coating were studied. The results indicate that the composition of LZ7C3 coating deviates from the ingot through energy dispersive spectroscopy (EDS) detection, however, the X-ray diffraction (XRD) pattern of the coating is similar with the ingot. By CeO2 adulteration, the linear thermal expansion coefficient (TEC) of LZ7C3 bulk is larger than that of La2Zr2O7 (LZ), and the isothermal oxidation performance of the LZ7C3 coating is superior to that of traditionally zirconia containing 8%(mass fraction) yttria (8YSZ) after isothermally oxidized at 1100℃ for 890h. The failure of the LZ7C3 coating is mainly a result of the TEC mismatch, the abnormal oxidation of bond coat and the occurrence of micro-cracks inside ceramic topcoat.