大气等离子喷涂热障涂层高温氧化行为研究

High Temperature Oxidation Behavior of APS Thermal Barrier Coatings

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。

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.