Development and Evaluation of Ceramic Components for Gas Turbine

Abstract

An 8000 kW class Hybrid Gas Turbine (HGT) project, administered by the New Energy and Industrial Technology Development Organization (NEDO), has been ongoing since July of 1999 in Japan. Targets of this project are improvement in thermal efficiency and output power by using ceramic components, and early commercialization of the gas turbine system. The ceramic components are used for stationary parts subjected to high temperature, such as combustor liners, transition ducts, and first stage turbine nozzles. Development of the gas turbine is conducted by Kawasaki Heavy Industries, Ltd. (KHI), to achieve the Turbine Inlet Temperature (TIT) of 1250°C, thermal efficiency of 34%, NOx emission less than standard regulation values, and 4,000 h engine durability. Kyocera is in charge of the development and evaluation of the ceramic components. Recently, recession of the Si based ceramic materials under the combustion gas is the focus of attention to improve the reliability of ceramic components for gas turbine. For the HGT project, the silicon nitride material (SN282 : silicon nitride material produced by Kyocera Corporation) is used for the components subjected to high temperature. The SN282 was evaluated under the combustion gas, and clear recession was observed. Our technology of the Environmental Barrier Coating (EBC) is under development to obtain reliable heat resistive SN282 components, against the recession by combustion gas. Reliability of the SN282 with EBC has been evaluated by exposure and hydrothermal corrosion test. Ceramic components made of SN282 with EBC will be also evaluated by a proof engine test of 4,000 h, which starts in the spring of 2002.