کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
1548166 997723 2016 9 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Microstructural evolution and growth kinetics of thermally grown oxides in plasma sprayed thermal barrier coatings
ترجمه فارسی عنوان
تکامل میکرو سازگار و سینتیک رشد از اکسید های گرمازده در پوشش های حرارتی اسپری
موضوعات مرتبط
مهندسی و علوم پایه مهندسی مواد مواد الکترونیکی، نوری و مغناطیسی
چکیده انگلیسی

The formation of thermally grown oxide (TGO) during high temperature is a key factor to the degradation of thermal barrier coatings (TBCs) applied on hot section components. In the present study both the CoNiCrAlY bond coat and ZrO2-8 wt.% Y2O3 (8YSZ) ceramic coat of TBCs were prepared by air plasma spraying (APS). The composition and microstructure of TGO in TBCs were investigated using scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS) and X-ray diffraction (XRD) analysis. The growth rate of TGO for TBC and pure BC were gained after isothermal oxidation at 1100 °C for various times. The results showed that as-sprayed bond coat consisted of β and γ/γ′phases, β phase reducesd as the oxidation time increased. The TGO comprised α-Al2O3 formed in the first 2 h. CoO, NiO, Cr2O3 and spinel oxides appeared after 20 h of oxidation. Contents of CoO and NiO reduced while that of Cr2O3 and spinel oxides increased in the later oxidation stage. The TGO eventually consisted of a sub-Al2O3 layer with columnar microstructure and the upper porous CS clusters. The TGO growth kinetics for two kinds of samples followed parabolic laws, with oxidation rate constant of 0.344 μm/h0.5 for TBCs and 0.354 μm/h0.5 for pure BCs.

ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Progress in Natural Science: Materials International - Volume 26, Issue 1, February 2016, Pages 103–111
نویسندگان
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