ZrO2-5%CaO TERMAL BARİYER KAPLAMA (TBC) SİSTEMİNİN SICAK KOROZYON DİRENCİ

Yıl 2020, Cilt: 7 Sayı: 2, 628 - 638, 31.05.2020

Kadir Mert Döleker

https://doi.org/10.31202/ecjse.686443

Cited By: 1

Öz

Termal bariyer kaplamalar (TBCs), yüksek sıcaklık koşullarında metalik altlık malzemeleri termal ve korozif koruma sağlamaktadır. TBC sistemleri, iş parçalarının sıcak bölüm komponentlerinde oksidasyon ve sıcak korozyon hasarlara maruz kalmaktadır. Özellikle sıcak korozyon, oksidasyona nazaran daha erken yıpratıcı hasarlara neden olmaktadır. Bu çalışmada, NiCoCrAlY tozları, yüksek hız oksi yakıt (HVOF) tekniği kullanılarak 316L paslanmaz çelik altlık malzeme üzerine püskürtülmüştür. Kalsiya ile stabilize zirkonya (ZrO2-5% CaO, CSZ), bağ kaplaması üretilmiş altlıklar üzerine üst kaplama malzemesi olarak atmosferik plazma sprey tekniği (APS) ile biriktirilmiştir. Üretilen TBC sistemi, 900 ° C' de % 50 V2O5-50 Na2SO4 karışımı ile 25 saatlik çevrimli sıcak korozyon testlerine tabi tutulmuştur. Sıcak korozyon testlerinin sonunda TBC sistemlerinde korozyon etkisi ve faz analizi stereo mikroskop, taramalı elektron mikroskobu (SEM), SEM - Enerji Dağılımlı X-Ray (EDX), SEM Haritalama ve XRD analizi kullanılarak incelenmiştir.

Anahtar Kelimeler

Sıcak korozyon, Termal bariyer kaplama, CaO-ZrO2, V2O5, Ergimiş tuz

Teşekkür

10-12 Ekim 2019 tarihlerinde Gaziantep Üniversitesi'nde düzenlenen TICMET19 konferansında sunulan çalışmamın seçilmesinde TICMET19 organizasyon komitesine en derin teşekkürümü sunuyorum.

Hot Corrosion Resistance of ZrO2-5%CaO Thermal Barrier Coating (TBC) System

Öz

Thermal barrier coatings (TBCs) provide thermal and corrosive protection to metallic substrate materials under high temperature conditions. TBC systems applied to hot part components of workpieces are exposed to oxidation and hot corrosion damage. Hot corrosion, in particular, causes destructive damage earlier than oxidation. In this study, NiCoCrAlY powders were sprayed on 316L stainless steel substrate material using High Velocity Oxygen Fuel (HVOF) technique. Calcia-stabilized zirconia (ZrO2-5% CaO, CSZ) was deposited as a top coating material by the atmospheric plasma spray technique (APS) on the substrate with the bond coat. The produced TBC system was subjected to 25 hours cyclic hot corrosion tests with a mixture of 50% V2O5- 50% Na2SO4 at 900 °C. At the end of the hot corrosion tests, as a result of the reaction of CaO with hot corrosion salts, phase transformation has occurred in the top coating. It has been found that the molten corrosion salts penetrate through the top coating, but have not yet seriously damaged the coating under these test conditions.

Anahtar Kelimeler

Hot corrosion; Thermal barrier coating (TBC); CaO-ZrO2; V2O5; Molten salt.

Kaynakça

• Doleker, K. M., Ozgurluk, Y., Ahlatci, H., Karaoglanli, A. C., Evaluation of oxidation and thermal cyclic behavior of YSZ, Gd2Zr2O7 and YSZ/Gd2Zr2O7 TBCs, Surface And Coatings Technology, 2019, 371, 262–275.
• Padture, N. P., Thermal Barrier Coatings for Gas-Turbine Engine Applications, Science, 2002, 296 (5566), 280–284.
• Karaoglanli, A. C., Doleker, K. M., Ozgurluk, Y., "State of the art thermal barrier coating (TBC) materials and tbc failure mechanisms", Advanced Structured Materials, Springer, Singapore, 2017, 441–452.
• Wortman, D. J., Fryxell, R. E., Luthra, K. L., Bergman, P. A., Mechanism of low temperature hot corrosion: Burner rig studies, Thin Solid Films, 1979, 64(2), 281–288.
• Eliaz, N., Shemesh, G., Latanision, R. M., Hot corrosion in gas turbine components, Engineering Failure Analysis, 2002, 9(1), 31–43.
• Hui, Y., Zhao, S., Xu, J., Zou, B., Wang, Y., Cai, X., Zhu, L., Cao, X., High-temperature corrosion behavior of zirconia ceramic in molten Na2SO4+NaVO3 salt mixture, Ceramics International, 2016, 42(1), 341–350.
• Habibi, M. H., Wang, L., Guo, S. M., Evolution of hot corrosion resistance of YSZ, Gd2Zr2O7, and Gd2Zr2O7+YSZ composite thermal barrier coatings in Na2SO4+V2O5 at 1050°C, Journal of The European Ceramic Society, 2012, 32(8), 1635–1642.
• Ozgurluk, Y., Doleker, K. M., Karaoglanli, A. C., Hot corrosion behavior of YSZ, Gd2Zr2O7 and YSZ/Gd2Zr2O7 thermal barrier coatings exposed to molten sulfate and vanadate salt, Applied Surface Science, 2018, 438, 96–113.
• Ozgurluk, Y., Doleker, K. M., Karaoglanli, A. C., Investigation of the effect of V2O5 and Na2SO4 melted salts on thermal barrier coatings under cyclic conditions, Anti-Corrosion Methods And Materials, 2019, 66(5), 644–650.
• Keyvani, A., Saremi, M., Heydarzadeh Sohi, M., Microstructural stability of zirconia-alumina composite coatings during hot corrosion test at 1050 °C, Journal of Alloys and Compounds, 2010, 506(1), 103–108.
• Wang, P., Deng, S., He, Y., Liu, C., and Zhang, J., Oxidation and hot corrosion behavior of Al2O3/YSZ coatings prepared by cathode plasma electrolytic deposition, Corrosion Science, 2016, 109, 13–21.
• Worrel, W. L., Solid Electrolytes, Springer-Verlag, New York, 2006, 143–166.
• Evans, H. E., Oxidation failure of TBC systems: An assessment of mechanisms, Surface and Coatings Technology, 2011, 206(7), 1512–1521.
• Toscano, J., Naumenko, D., Gil, A., Singheiser, L., Quadakkers, W. J., Parameters affecting TGO growth rate and the lifetime of TBC systems with MCrAIY-bondcoats, Materials and Corrosion, 2008, 59(6), 501–507.
• Doleker, K. M., Ozgurluk, Y., Karaoglanli, A. C., Isothermal oxidation and thermal cyclic behaviors of YSZ and double-layered YSZ/La2Zr2O7 thermal barrier coatings (TBCs), Surface and Coatings Technology, 2018, 351, 78–88.
• Doleker, K. M., Ahlatci, H., Karaoglanli, A. C., Investigation of Isothermal Oxidation Behavior of Thermal Barrier Coatings (TBCs) Consisting of YSZ and Multilayered YSZ/Gd2Zr2O7 Ceramic Layers, Oxidation of Metals, 2017, 88(1–2), 109–119.
• Liu, Z. G., Ouyang, J. H., Zhou, Y., Xia, X. L., Hot corrosion behavior of V2O5-coated Gd2Zr2O7 ceramic in air at 700-850 °C, Journal of The European Ceramic Society, 2009, 29(11), 2423–2427.
• Park, S. Y., Kim, J. H., Kim, M. C., Song, H. S., Park, C. G., Microscopic observation of degradation behavior in yttria and ceria stabilized zirconia thermal barrier coatings under hot corrosion, Surface and Coatings Technology, 2005, 190(2–3), 357–365.
• Afrasiabi, A., Saremi, M., Kobayashi, A., A comparative study on hot corrosion resistance of three types of thermal barrier coatings: YSZ, YSZ+Al2O3 and YSZ/Al2O3", Materials Science and Engineering A, 2008, 478(1–2), 264–269.
• Ahmadi-Pidani, R., Shoja-Razavi, R., Mozafarinia, R., Jamali, H., Evaluation of hot corrosion behavior of plasma sprayed ceria and yttria stabilized zirconia thermal barrier coatings in the presence of Na2SO4+V2O5 molten salt, Ceramics International, 2012, 38(8), 6613–6620.