Microstructural features and properties of plasma sprayed YPSZ/NiCrAlY thermal barrier coating (TBC)

作     者：孙大谦 王文权 宣兆志 宫文彪 

作者机构：Key Laboratory of Automobile Materials Jilin University Changchun 130025 

出 版 物：《China Welding》 (中国焊接（英文版）)

年 卷 期：2004年第13卷第2期

页      面：91-96页

核心收录：

学科分类：080503[工学-材料加工工程] 08[工学] 0805[工学-材料科学与工程（可授工学、理学学位）] 

基　　金：ThisworkwasfinanciallysupportedbythefoundationsoftheNationalDefenseTechnologyKeyLaboratoryandNationalModernWeldingTechnologyKeyLaboratory 

主　　题：plasma spray thermal barrier coating microstructure properties 

摘      要：The plasma sprayed thermal barrier coating (TBC) consists of NiCrAlY bond coating and yttria partially stabilized zirconia (YPSZ) top coating. NiCrAlY coating mainly contains Ni solid solution with face centered cubic lattice, Al_2O_3 oxides and pores. The most obvious feature of YPSZ coating with tetragonal zirconia is a lot of vertical microcracks in this coating. The thermal insulation capability of the TBC increased with an increase in YPSZ coating thickness, the temperature drop across the TBC increasing from 60℃ to 92℃ with increasing YPSZ coating thickness from 100 μm to 500 μm. The thermal shock resistance of the TBC decreased with increasing YPSZ coating thickness and cracks initiated mainly in original vertical microcrack tips of the YPSZ coating and propagated not only along YPSZ coating/ NiCrAlY coating interface but also through NiCrAlY coating. The oxidation process of the TBC at 1 200℃ can be divided into two stages: transient oxidation stage with rapid oxidation rate and steady oxidation stage with slow oxidation. Their transition time was about 10 hours. The weight gain for 100 hours was 3.222 mg/mm2. It is favorable to increase YPSZ coating toughness and to decrease the pores and oxides of the TBC system for improving thermal shock resistance and oxidation resistance of the TBC.