Thermal Diffusivity and Conductivity of Yttria Stabilized Zirconia Coatings Obtained by Suspension Plasma Spraying
Thermal Diffusivity and Conductivity of Yttria Stabilized Zirconia Coatings Obtained by Suspension Plasma Spraying
复制标题
DOI：
10.1016/j.surfcoat.2012.08.014
复制
发表时间：
2012-05
期刊：
影响因子：
--
通讯作者：
L. Łatka;Andrea Cattini;L. Pawłowski;S. Valette;B. Pateyron;J. Lecompte;Rishi Kumar;A. Denoirjean
中科院分区：
文献类型：
--
作者：
L. Łatka;Andrea Cattini;L. Pawłowski;S. Valette;B. Pateyron;J. Lecompte;Rishi Kumar;A. Denoirjean
SG-100焊枪产生的等离子体应用于ZrO2+8wt配制的喷雾悬浮液中。% Y2O3（8YSZ）固相。该固体的平均尺寸约为4.5μm，由Metco 204NS粉末研磨而成。该悬浮液是用20wt配制的。%的固相，40wt。%水和40wt。%乙醇。在电功率为40kW，工作气体成分为Ar-45slpm和H2-5slpm，喷射距离为40 ~ 60mm，喷枪相对基材线速度为300 ~ 500mm/s的条件下，对等离子体喷射参数进行了优化。在不锈钢基体上喷涂了厚度为51 ~ 106μm的涂层。通过对样品的金相制备截面进行图像分析，发现样品的孔隙率在8-12%之间。使用商用NanoFlash系统在室温至523K的温度范围内测量热扩散率。利用喷涂在基材上的涂层进行了测量，并采用两层数值模型确定了涂层的热扩散系数。在室温下，扩散系数随喷雾参数的变化范围为0.196×10−6 ~ 0.352×10−6m2/s。然后将获得的数据与密度、比热和实验孔隙率的文献数据相关联，得出室温下的导热系数在0.47至0.86W/(mK)之间，具体取决于喷涂运行情况。
Plasma generated by SG-100 torch was applied to spray suspension formulated with the use of ZrO2+8wt.% Y2O3(8YSZ) solid phase. The solids have the mean size of about 4.5μm and were obtained by milling commercial Metco 204NS powder. The suspension was formulated with the use of 20wt.% of solid phase, 40wt.% water and 40wt.% of ethanol. The plasma spray parameters were optimized with the electric power equal to 40kW, working gases composition Ar—45slpm and H2—5slpm, spray distance varying from 40 to 60mm and torch linear speed with regard to substrate varying from 300 to 500mm/s. The coatings of the thickness ranging from 51 to 106μm, were sprayed onto stainless steel substrates. The porosity of the samples was found, with the help of image analysis of metallographically prepared cross-sections of the samples, to be in the range of 8–12%. Thermal diffusivity was measured with the use of the commercial NanoFlash system in the temperature range from room temperature to 523K. The measurements were made with the use of the coatings sprayed on the substrate and the 2-layers numerical model was applied to determine thermal diffusivity of the coatings. The diffusivity was in the range 0.196×10−6to 0.352×10−6m2/s in room temperature depending on the spray parameters. The obtained data were then associated with the literature data on density, specific heat and experimental porosity to find thermal conductivity which was in the range of 0.47 to 0.86W/(mK) at room temperature depending on the spray run.