Ultrasonic technologies offer the potential for high
accuracy and resolution in-pile measurement of numerous
parameters, including geometry changes, temperature, crack
initiation and growth, gas pressure and composition, and
microstructural changes. Many Department of Energy-Office of
Nuclear Energy (DOE-NE) programs are exploring the use of
ultrasonic technologies to provide enhanced sensors for in-pile
instrumentation during irradiation testing. For example, the
ability of single, small diameter ultrasonic thermometers (UTs) to
provide a temperature profile in candidate metallic and oxide
fuel would provide much needed data for validating new fuel
performance models. Other efforts include an ultrasonic
technique to detect morphology changes (such as crack initiation
and growth) and acoustic techniques to evaluate fission gas
composition and pressure. These efforts are limited by the lack of
existing knowledge of ultrasonic transducer material
survivability under irradiation conditions.
To address this need, the Pennsylvania State University (PSU)
was awarded an Advanced Test Reactor National Scientific User
Facility (ATR NSUF) project to evaluate promising
magnetostrictive and piezoelectric transducer performance in the
Massachusetts Institute of Technology Research Reactor (MITR)
up to a fast fluence of at least 1021 n/cm2 (E> 0.1 MeV).
This test will be an instrumented lead test; and real-time
transducer performance data will be collected along with
temperature and neutron and gamma flux data. By
characterizing magnetostrictive and piezoelectric transducer
survivability during irradiation, test results will enable the
development of novel radiation tolerant ultrasonic sensors for use
in Material and Test Reactors (MTRs). The current work
bridges the gap between proven out-of-pile ultrasonic techniques
and in-pile deployment of ultrasonic sensors by acquiring the
data necessary to demonstrate the performance of ultrasonic
transducers