大气等离子喷涂热障涂层高温氧化行为研究

采用等离子喷涂工艺在GH4099合金基体上制备了热障涂层，并进行了1050℃恒温氧化试验，综合利用X射线衍射仪、扫描电子显微镜、能谱分析仪等检测手段，分析了涂层的显微结构及高温氧化行为。结果表明：等离子喷涂（APS）热障涂层在高温氧化过程中，黏结层被氧化生成热生长氧化物（TGO）。但长时间氧化后，在与TGO毗邻的金属黏结层中产生了范围较窄但浓度变化较大的贫Al带，TGO层出现保护性Al2O3向非保护性混合氧化物转变的现象，导致致密Al2O3层的连续性被破坏，TGO厚度快速增加。

High Temperature Oxidation Behavior of APS Thermal Barrier Coatings

Thermal barrier coatings （TBCs） were deposited onto GH4099 alloy by the atmospheric plasma spraying （APS） and the constant temperature oxidization test was also performed at 1050℃. The microstructure and high temperature oxidation behavior of atmospheric plasma spraying thermal barrier coatings were investigated using the scanning electron microscope （SEM）, energy dispersive spectroscopy （EDS） and X-ray diffraction （XRD）. The results show that thermally grown oxide （TGO ）was formed for the oxidation of bond coat during high temperature oxidization of APS TBC. But, aluminum-depleted area was found in the bond coat next to TGO which was more narrow and change largely with concentration range offer long time oxidation. The transition phenomena from protective A l2O3 to non- protective oxide in TGO player was appeared which destroyed the continuity of the compact Al2O3 layer and TGO layer growing rapidly.