Predicting the Reliability of Ceramic Turbine Components

Detroit Diesel Allison is developing ceramic hot flowpath components for application in small vehicular industrial gas turbine engines. A key element of this program is the development of an appropriate methodology for predicting component reliability. This paper discusses the elements of the established methodology and compares predicted and measured reliabilities of a blade attachment spin test coupon in order to assess the validity of analysis techniques. Included are summaries of methods used to obtain and analyse material strength characteristics, finite element modeling technique, blade coupon reliability computations, blade coupon spin test results and failure analyses.