摘要：利用大氣等離子噴涂制備了ZrO2涂層, 采用掃描電子顯微鏡結(jié)合圖像分析的方法對(duì)涂層的顯微結(jié)構(gòu)特征(總氣孔率和大氣率)進(jìn)行了量化表征。同時(shí)利用掃描電子顯微鏡附帶X射線掃描成像對(duì)涂層內(nèi)部的微裂紋和大的分隔裂紋的三維分布進(jìn)行了表征。據(jù)此建立了ZrO2涂層顯微結(jié)構(gòu)與熱導(dǎo)率之間的關(guān)系。室溫下, 涂層N2的熱導(dǎo)率較N1的低, 因?yàn)橥繉覰2內(nèi)氣孔和微裂紋數(shù)較多；在1000℃, 由于微裂紋的燒結(jié)作用導(dǎo)致熱導(dǎo)率增大, 所以涂層N2的熱導(dǎo)率較N1反而高。高溫下, 涂層內(nèi)由微裂紋匯聚而形成的大的分隔裂紋的存在則可以有效地抑制燒結(jié), 降低涂層的熱導(dǎo)率。

       Abstract：Yttria stabilized zirconia coatings were deposited using two different sets of parameters (N1, N2 coating).The microstructure features, such as total porosity and large porosity, were quantified by means of scanning electronmicroscope and image analysis. The three-dimensional distribution of microcracks and segmentation cracks was successfully revealed by the X-ray microscopy in the scanning electron microscope with three-dimensional microtomography capability. So the relationship between microstructure and thermal conductivity was found. At room temperature, thermal conductivity of N2 was lower than that of N1 due to larger pores and microcracks. At 1000℃ thermal conductivity of N1 was lower for the sintering of microcracks. The segmentation cracks formed by the
propagation of microcracks could effectively reduce the thermal conductivity at high temperature.

       Key Word：ZrO2 coatings,microstructure,thermal conductivity,X-ray microscopy