Influence of Defect Orientation on Electrical Insulating Properties of Plasma-Sprayed Alumina Coatings
Influence of Defect Orientation on Electrical Insulating Properties of Plasma-Sprayed Alumina Coatings
复制标题
缺陷取向对等离子喷涂氧化铝涂层电绝缘性能的影响
DOI：
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发表时间：
2005
期刊：
影响因子：
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通讯作者：
R. Saenger
中科院分区：
文献类型：
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作者：
S. Beauvais;V. Guipont;M. Jeandin;D. Juvé;D. Tréheux;A. Robisson;R. Saenger
采用扫描电子显微镜镜面效应（SEMME）技术研究了等离子喷涂氧化铝涂层的微观结构（孔隙和裂纹）对涂层电性能的影响。使用CAPS（“可控气氛等离子喷涂”）在不同的气氛下喷涂不同的氧化铝原料粉末。分析了不同孔隙率下的微观组织和裂纹取向分布。利用两种互补模式（吸收电流测量和镜面法），利用SEMME技术分析了氧化铝涂层的外表面和横截面。SEMME技术最初是为了研究注入电子的行为和相关现象，如大块绝缘材料中的捕获能力、脱陷过程和弛豫现象，在这项研究中，SEMME技术成功地应用于多孔涂层。实验证明，裂纹取向改变了电荷的运动和俘获，从而改变了等离子喷涂氧化铝涂层的介电性能。
The influence of the microstructure (pores and cracks) on electric properties of plasma-sprayed alumina coatings was investigated using the so-called Scanning Electron Microscope Mirror Effect (SEMME) technique.Coatings were sprayed with different alumina feedstock powders on various atmospheres using a CAPS (‘Controlled Atmosphere Plasma Spraying’). Microstructures with various amount of porosity and cracks orientation distributions were analysed. Both outer surfaces and cross-sections of alumina coatings have been analysed by SEMME technique using two complementary modes (measurement of absorbed current and mirror methods). Originally developed to study the behaviour of injected electrons and related phenomena, such as trapping ability, detrapping process and relaxation phenomena in bulk insulating materials, the SEMME technique was successfully applied, in this study, to porous coatings. It is proved that cracks orientation modifies both motion and trapping of charges and therefore the dielectric properties of plasma-sprayed alumina coatings.