Author/Authors :
KARAOĞLANLI, Abdullah Cahit Bartın Üniversitesi - Mühendislik-Mimarlık Fakültesi - Metalurji ve Malzeme Mühendisliği Bölümü, Turkey , TÜRK, Ahmet Sakarya Üniversitesi - Mühendislik-Mimarlık Fakültesi - Metalurji ve Malzeme Mühendisliği Bölümü, Turkey , ÖZDEMİR, Ismail İzmir Katip Çelebi Üniversitesi - Mühendislik Fakültesi - Malzeme Bilimi ve Mühendisliği Bölümü, Turkey
Title Of Article :
Investigation of Oxidation Behavior of Plasma Sprayed Ceramic Based Coatings
Abstract :
Thermal barrier coatings (TBCs) are widely used in aviation industry in order to protect components such as turbine blades and vanes in gas turbine engines from oxidation and corrosion failures occurring by the effect of high temperature and to provide high performance and efficiency in turbines. A TBC system is generally consist of a MCrAlY based metallic bond coat deposited on superalloy substrate and a ceramic topcoat deposited on this bond coat. In this system, the metallic bond coat both provides adhesion of ceramic topcoat on the substrate and protects the substrate material from oxidation and corrosion failures, while the ceramic topcoat provides thermal insulation. In this study, in order to simulate service conditions of gas turbines, CoNiCrAlY based metallic bond coat and yitriya stabilized zirconia (YSZ) topcoat structure were deposited on superalloy substrate by atmospheric plasma spray (APS) technique, and a TBC system was generated. Oxidation tests of the TBC structure were conducted for different time periods at 1000 °C. Microstructural change in TBCs after oxidation were examined using scanning electron microscope (SEM). Thermal grown oxide (TGO) layer formed at bond coat/topcoat interface after oxidation tests. It was seen that an oxide (TGO) layer, which occurs at bond and top coat interface and grows thermally up, forms after oxidation test. The thickness of oxide layer increased with the increasing oxidation time.
NaturalLanguageKeyword :
“Thermal barrier coating (TBC)” , “Oxidation” , “YSZ” , “CoNiCrAlY” , “Plasma spray coatings” , “Microstructure”
JournalTitle :
Afyon Kocatepe University Journal Of Science and Engineering
