等离子喷涂纳米复合陶瓷涂层的研究

Nanostructured Composite Ceramic Coating Sprayed by Plasma

借助扫描电镜和能谱分析,观测了等离子喷涂Al2O3-13%TiO2+ZrO2+CeO2纳米复合陶瓷涂层的显微组织和微区成分;通过硬度检测和相分析,研究了250℃和500℃低温退火对涂层硬度、晶粒度、断裂韧性以及相组成的影响。结果表明,纳米涂层呈层状结构,空隙率较低,且具有较高的硬度和结合强度;上述低温退火虽降低了纳米陶瓷涂层的显微硬度,但使其断裂韧性明显提高,而且对涂层的相组成和晶粒度影响不大。

A nanostructured Al2O3-13%TiO2＋ZrO2＋CeO2 composite ceramic coating was deposited by plasma spray technique. The microstructures and local elements of the nano-coating were studied by means of scanning electron microscope （SEM） and energy dispersive spectrometry （EDS）. The effect of annealing treatments at 250℃ and 500℃ on the microhardness, indentation cracks, and phase composition of the nano-coating were investigated by hardness-testing and X-ray diffraction （XRD） analysis. The results show that a good compactness and a higher bonding strength to the substrate are achieved in the nano-coating; moreover, the annealing treatments can markedly improve fracture toughness of the nano-coating despite decreasing its microhardness.