{"title":"The Oxidation Behaviors of NiCoCrAlY Coatings After Pre-Oxidation Treatment During High-Temperature Oxidation at 800 ℃ and 900 ℃","authors":"Masahiro Negami, Yoko Yamabe-Mitarai","doi":"10.1007/s11085-024-10221-6","DOIUrl":null,"url":null,"abstract":"<div><p>Thermal barrier coatings (TBCs) are essential for protecting the high-temperature components in gas turbines. However, the durability of TBCs is limited, and new technologies to improve their lifetime are necessary. This study focuses on the pre-oxidation treatment of the NiCoCrAlY bond coat in TBCs to reduce the growth rate of the thermally grown oxide (TGO) and improve the TBC lifetime. The mechanism of the TGO growth rate reduction by the pre-oxidation treatment of NiCoCrAlY was investigated. Oxidation behaviors of the surface of NiCoCrAlY coating samples with or without pre-oxidation treatment were evaluated in air at 800 °C and 900 °C. In-situ X-ray diffraction (XRD) measurements and isothermal oxidation tests were performed. The obtained results revealed that the growth rate of TGO is significantly suppressed by <i>α</i>-Al<sub>2</sub>O<sub>3</sub> layer formed by the pre-oxidation treatment. The generation of <i>γ</i>-Al<sub>2</sub>O<sub>3</sub> and <i>θ</i>-Al<sub>2</sub>O<sub>3</sub>, which are typically formed below 900 °C, was significantly reduced by pre-oxidation. It is suggested that this reduction suppresses of the TGO growth.</p></div>","PeriodicalId":724,"journal":{"name":"Oxidation of Metals","volume":null,"pages":null},"PeriodicalIF":2.1000,"publicationDate":"2024-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s11085-024-10221-6.pdf","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Oxidation of Metals","FirstCategoryId":"88","ListUrlMain":"https://link.springer.com/article/10.1007/s11085-024-10221-6","RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q2","JCRName":"METALLURGY & METALLURGICAL ENGINEERING","Score":null,"Total":0}
引用次数: 0
Abstract
Thermal barrier coatings (TBCs) are essential for protecting the high-temperature components in gas turbines. However, the durability of TBCs is limited, and new technologies to improve their lifetime are necessary. This study focuses on the pre-oxidation treatment of the NiCoCrAlY bond coat in TBCs to reduce the growth rate of the thermally grown oxide (TGO) and improve the TBC lifetime. The mechanism of the TGO growth rate reduction by the pre-oxidation treatment of NiCoCrAlY was investigated. Oxidation behaviors of the surface of NiCoCrAlY coating samples with or without pre-oxidation treatment were evaluated in air at 800 °C and 900 °C. In-situ X-ray diffraction (XRD) measurements and isothermal oxidation tests were performed. The obtained results revealed that the growth rate of TGO is significantly suppressed by α-Al2O3 layer formed by the pre-oxidation treatment. The generation of γ-Al2O3 and θ-Al2O3, which are typically formed below 900 °C, was significantly reduced by pre-oxidation. It is suggested that this reduction suppresses of the TGO growth.
期刊介绍:
Oxidation of Metals is the premier source for the rapid dissemination of current research on all aspects of the science of gas-solid reactions at temperatures greater than about 400˚C, with primary focus on the high-temperature corrosion of bulk and coated systems. This authoritative bi-monthly publishes original scientific papers on kinetics, mechanisms, studies of scales from structural and morphological viewpoints, transport properties in scales, phase-boundary reactions, and much more. Articles may discuss both theoretical and experimental work related to gas-solid reactions at the surface or near-surface of a material exposed to elevated temperatures, including reactions with oxygen, nitrogen, sulfur, carbon and halogens. In addition, Oxidation of Metals publishes the results of frontier research concerned with deposit-induced attack. Review papers and short technical notes are encouraged.