This work describes the results of experiments conducted a part of an instrumented lead test in-core in a nuclear reactor with the piezoelectric and magnetostrictive materials. The experiments exposed AlN, ZnO, BiT, Remendur, and Galfenol to more neutron radiation than found in the literature. The magnetostrictive sensors produce stable ultrasonic pulse-echoes throughout much of the irradiation. The BiT transducer could operate up until approximate 5 ×10⁁20 n/cm⁁2 (E>1MeV). The piezoelectric AlN operated well during the entire experiment. The results imply that now available are candidates for operation in a harsh environments found in nuclear reactors and steam generator plants.