Effects of Heat Exposure Time and Temperature on the Delamination Behavior of Air Plasma-Sprayed Thermal Barrier Coatings under Shear Loading

• Hasegawa Makoto

  Division of Materials Science and Chemical Engineering, Faculty of Engineering, Yokohama National University

• Endo Tsuyoshi

  Division of Materials Science and Chemical Engineering, Faculty of Engineering, Yokohama National University

• Fukutomi Hiroshi

  Division of Materials Science and Chemical Engineering, Faculty of Engineering, Yokohama National University

抄録

The delamination behavior of air plasma-sprayed thermal barrier coatings (APS-TBCs) exposed to heat in air at different temperatures was evaluated under mode II loading conditions. The TBC layer, BC layer, and substrate were composed of 8 mass% Y₂O₃ partially stabilized ZrO₂, NiCoCrAlY alloy, and Inconel 738 nickel base superalloy. The heat exposure was performed at 1173 K or 1423 K for 10 to 200 h. During the heat exposure, the thickness of thermally grown oxide (TGO) increased and the hardness of the bond coat (BC) layer near the TGO decreased with increasing heat exposure time. The delamination toughness decreased monotonically with increasing heat exposure time when the TBCs were heat exposed at 1173 K. In this case, delamination occurred at the TBC layer. The average thickness of the remaining TBC on the substrate side decreased with increasing exposure time. As for the TBCs exposed at 1423 K, the delamination toughness increased over the first 50 h, but then began to decrease with further exposure time. The delamination pathway has transferred to near the TGO layer. The fraction of TBC layer fracture decreased, whereas those of the TBC/TGO interface and TGO/BC interface fracture increased with increasing exposure time. The change in delamination toughness may have been caused by the interaction between the TGO thickening and the reduction of BC layer hardness. The increase in TGO thickness decreased the delamination toughness due to an increase in residual stresses. The decrease in hardness of the BC layer near the TGO may have increased the delamination toughness by increasing the plastic dissipation.

収録刊行物

• MATERIALS TRANSACTIONS

  MATERIALS TRANSACTIONS 57 (7), 1138-1146, 2016

  公益社団法人 日本金属学会

キーワード

• air plasma-sprayed thermal barrier coatings
• interfacial delamination toughness
• mode II loading condition
• plastic dissipation
• pushout test

詳細情報

• CRID: 1390282679231514880
• NII論文ID: 130005158402
• NII書誌ID: AA1151294X
• DOI: 10.2320/matertrans.m2016077
• ISSN: 13475320
• ISSN: 13459678
• NDL書誌ID: 027448368
• Web Site: http://hdl.handle.net/10131/10234
• Web Site: https://ndlsearch.ndl.go.jp/books/R000000004-I027448368
• Web Site: https://www.jstage.jst.go.jp/article/matertrans/57/7/57_M2016077/_pdf
• 本文言語コード: en
• データソース種別:
  • JaLC
  • IRDB
  • NDL
  • Crossref
  • CiNii Articles
• 抄録ライセンスフラグ: 使用不可