多層遮熱コーティング材の衝撃加振による 高温下弾性率測定システムの開発

抄録

Gas turbines of power generation systems used in high-temperature environments are expected to improve their thermal efficiency by increasing the turbine inlet temperature. In such environments, thermal barrier coating of turbine blades has become an indispensable material technology. In this study, the elastic moduli of the thermal barrier coatings were measured at high temperatures up to 1000 ℃. Experiments and finite element analysis were performed using a rectangular section bar with a metal substrate coated with two layers, that is, a metallic bond coat and a ceramic top coat. The elastic modulus of each layer is calculated from the natural frequency of the specimen by applying the multilayer beam theory for the flexural free vibration. The elastic moduli of the substrate, the bond coat and the top coat in the cooling down process after heating at 1000 ℃ increased as the temperature decreased.