# Detection of Micro-Damage Evolution of Air Plasma-Sprayed Y_2O_3-ZrO_2 Thermal Barrier Coating through TGO Stress Measurement

## 抄録

The micro damage evolution behavior in air plasma-sprayed 8mass% $Y_{2}0_{3}$ stabilized Zr$O_{2}$ thermal barrier coating (APS-TBC) after isothermal heat exposure at 1150℃ up to 200h was observed. Residual stress of thermally-grown-oxide (TGO) layer was measured though the TBC layer using Cr^3+ luminescence spectroscopy and the measured stress levels were compared with microdamage evolution behavior stored in the TBC system. With heat exposure time of longer than 1Oh, microfracture behaviors were noted in the TBC layer. In-plane residual stress of the TGO layer increased for up to 50h of heat exposure time, and thereafter, diminished with further increase. These behaviors are strongly correlated with the thickness and the residual stress of the TGO layer. This decrease in the TGO stress well contrasts with the evolution of the micro fracture behavior, which is also related to the thickness and undulation of the formed TGO layer. The change of TGO stress $σ_{tgo}$, depending on the average thickness of the_TGO layer, $overline{h}_{tgo}$, {\iti.e.}, d$σ_{tgo}/d$overline{h}_{tgo}$is a useful indicator of the damage evolution in TGO： d$σ_{tgo}/d$overline{h}_{tgo}$ > 0: slight damage stage, d$σ_{tgo}$/d$overline{h}_{tgo}$ < 0: micro fracture evolution stage. The result suggests that Cr^3+ luminescence spectroscopy is a good indicator for micro damage evolution in the TBC layer and is a useful tool for nondestructive evaluation (NDE) of APS-TBC systems.

The micro damage evolution behavior in air plasma-sprayed 8 mass% Y<SUB>2</SUB>O<SUB>3</SUB> stabilized ZrO<SUB>2</SUB> thermal barrier coating (APS-TBC) after isothermal heat exposure at 1150°C up to 200 h was observed. Residual stress of thermally-grown-oxide (TGO) layer was measured through the TBC layer using Cr<SUP>3+</SUP> luminescence spectroscopy and the measured stress levels were compared with micro damage evolution behavior stored in the TBC system. With heat exposure time of longer than 10 h, microfracture behaviors were noted in the TBC layer. In-plane residual stress of the TGO layer increased for up to 50 h of heat exposure time, and thereafter, diminished with further increase. These behaviors are strongly correlated with the thickness and the residual stress of the TGO layer. This decrease in the TGO stress well contrasts with the evolution of the micro fracture behavior, which is also related to the thickness and undulation of the formed TGO layer. The change of TGO stress, σ<SUB><I>tgo</I></SUB>, depending on the average thickness of the TGO layer, \\bar<I>h</I><SUB><I>tgo</I></SUB>, <I>i.e.</I>, <I>d</I>σ<SUB><I>tgo</I></SUB>⁄<I>d</I>\\bar<I>h</I><SUB><I>tgo</I></SUB> is a useful indicator of the damage evolution in TGO: <I>d</I>σ<SUB><I>tgo</I></SUB>⁄<I>d</I>\\bar<I>h</I><SUB><I>tgo</I></SUB>>0: slight damage stage, <I>d</I>σ<SUB><I>tgo</I></SUB>⁄<I>d</I>\\bar<I>h</I><SUB><I>tgo</I></SUB><0: micro fracture evolution stage. The result suggests that Cr<SUP>3+</SUP> luminescence spectroscopy is a good indicator for micro damage evolution in the TBC layer and is a useful tool for nondestructive evaluation (NDE) of APS-TBC systems.

## 収録刊行物

• Materials transactions

Materials transactions 47(10), 2512-2517, 2006-10-20

公益社団法人 日本金属学会

## 各種コード

• NII論文ID(NAID)
10018310256
• NII書誌ID(NCID)
AA1151294X
• 本文言語コード
ENG
• 資料種別
ART
• ISSN
13459678
• NDL 記事登録ID
8092083
• NDL 雑誌分類
ZP41(科学技術--金属工学・鉱山工学)
• NDL 請求記号
Z53-J286
• データ提供元
CJP書誌  CJP引用  NDL  IR  J-STAGE

ページトップへ