Response of lead metaniobate acoustic emission sensors to gamma irradiation

Piezoelectric (PE) acoustic emission (AE) sensors were exposed to hundreds of kGy from Co-60 gamma rays. Recalibration of gamma-irradiated sensors showed a sensitivity decline of 8.4% per 100 kGy. Exposure of lead metaniobate disc specimens, the sensor ferroelectric material, to /spl sim/1 MGy revealed a capacitance increase and PE voltage (g/sub 33/) coefficient decrease with gamma dose. The planar coupling factor (k/sub p/) and mechanical quality factor (Q/sub m/) exhibited small reductions. The AE sensors were also subjected to nuclear radiation from a pulse reactor.