PRACTICAL ISSUES IN THE NDE OF ADVANCED CERAMICS

Abstract Practical issues raised by the necessity to NDE advanced-ceramic components are reviewed. Ultrasonic inspection is identified as the economically viable method and implications of ceramic inspection by transducers on the properties of the latter, are discussed. The high-frequency/high-power requirements have led to the synthesis of AIN piezoelectrics and these are discussed. Economics require array transducers and their development is outlined. The establishment of a database for the ultrasonic NDE of advanced-ceramic components is described. The probes developed were used to examine model spherical inclusions (voids (≥20μm), Zr02, MgO, and Pt inclusions (≥30μm)) in model matrices (glass, crystallized glass and partially stabilized zirconia). Surface breaking cracks were also analysed. Actual frequency spectra obtained from these defects as a function of defect size are compared with their calculated spectra and good agreement obtained.