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The application of ceramic components in gas turbine engines enables the improvement of the power output and the efficiency of gas turbines by increasing the turbine inlet temperature. The high temperature properties of the ceramic materials offer the potential of higher turbine operating temperatures with no cooling techniques and therefore the ceramic components with higher temperature limits are becoming more attractive. In this study, the ceramic turbine wheel is applied in the aircraft gas turbine engine and the engine testing is demonstrated under full load operating conditions. The successful testing of the ceramic turbine components in the aircraft gas turbine engine has been accomplished. The test results indicate that the ceramic turbine wheel is capable of operating under the high thermal shock condition of fast starting to full speed. Furthermore, the adoption of some new ceramic turbine design concepts is proposed in actual use for aircraft ceramic turbine engines.

In Japan, all large capacity fossil-fuel power plants are supercritical units and a steam condition of 24.1 MPag, 538/566°C has been adopted. Through extensive development work, the design and material technologies for steam turbines with a 593°C steam temperature have been established, and the steam condition of 24.1 MPag, 538/593°C was applied to the 700 MW steam turbine of Hekinan No. 3 Unit, Chubu Electric Power Co., Inc. for the first time in Japan. This unit has been operating successfully since it started commercial operation in April, 1993. Mitsubishi Heavy Industries, Ltd. (MHI) designed 1000 MW class turbines with more advanced steam conditions of 600°C class main steam and reheat steam temperatures for the first time in Japan, applying the latest technologies developed for 600°C class application.

In recent years, the turbine inlet temperature becomes higher and higher to grow up the power of gas turbine engines in recent years. So hot section parts, such as combustor and turbine, are generally designed as cooling structures made of heat resistant metals. On the other hand, the high temperature properties of the ceramic materials offer the potential of higher turbine operating temperatures with no cooling techniques and therefore the ceramic components with higher temperature limits are becoming more attractive. In this study, the ceramic turbine is applied in the aircraft gas turbine engine. For gas turbine engines, tight fit configuration is generally taken for the joint structure between a ceramic turbine and a metal shaft, and its constrain force transmits the drive torque and withstands the thrust force acted on the turbine. Since the constrain force is decreased due to the difference of the thermal expansion rate between ceramic and metal at the high temperature condition, the initial constrain force should be taken large enough considering the decrease of the constrain force. But if the fit is too tight, the ceramic turbine will be cracked at the jointing process. So an optimization is necessary to balance these