High temperature integrated ultrasonic transducers for engine condition monitoring

Employing a portable on-site fabrication kit, high temperature integrated ultrasonic transducers (IUTs) made of bismuth titanate piezoelectric film, of thickness greater than 50 \ub5m, have been caoted directly onto a modified CF700 turbojet engine outer casing, oil sump and supply lines and gaskets using sol-gel spray technology. Transducers top electrodes, electrical wires, conducting adhesive bond, connectors and cables have all been successfully tested for temperatures up to 500\ub0C. The excellent ultrasonic performance of these IUTs is demonstrated in this paper and the potential applications for the non-intrusive real-time temperature and lubricant oil quality and metal debris monitoring have been identified and discussed.Peer reviewed: NoNRC publication: Ye