Current progress in Japan of advanced ceramics for high temperature application

Abstract

The Ministry of International Trade and Industry (MITI) is currently promoting three national projects on high temperature structural ceramics. In the project of “Fine Ceramics” (1981-'92) part of “R & D of Basic Technologies for Future Industries”, silicon nitride and silicon carbide based ceramics are being developed for gas turbine components. This project puts emphasis on basic research on ceramic materials, particularly on the processing and is now in the final stages. The “Ceramic Gas Turbine (CGT) Project” (1988-'96) aims to establish 3 types of 300 KW CGT with turbine inlet temperature of 1350°C for industrial uses. “Automotive CGT Project” (1988-'96) is planned to develop an automotive CGT of 100 KW class and it is now in the stage of preliminary study for the first 2 years to be followed by 7 years full scale R & D. The engine type to be developed is presently under discussion. Those projects are carried on with close cooperation between industries and government research institutes. On application to ceramic gas turbine private sectors are carrying on their individual research work. Generally speaking, CGT research in Japan is at the stage of developing ceramic components. The fine ceramic market size is gradually increasing and it is expected that total production will be 6000 billion Yen in Japan by the year 2000. But the share of mechanical and high temperature ceramics is expected to be 10% of the total. However, as many users want high temperature structural ceramics for application to mechanical and thermal fields, it is thought that high temperature ceramic field will become more important in the future. However, many problems remain to be solved for industrial application of high temperature structural ceramics, such as improvement in strength, toughness, reliability, cost decrease, etc. One of the important future directions is considered to be research on ceramic composites by microstructural control with atomic and molecular level. And also we should consider applying the research results of other engineering fields and also use the results in general human activities.