b'irradiation is shown in Figure 1.ture provided valuable feedback for Electron microscopy was also usedsimulations of MiniFuel targets that to evaluate the microstructure andare currently being designed and secondary phases observed in thefabricated for insertion into HFIR.optical microscopy. All the phasesReferences:detected at this burnup were related[1.] D.C. Crawford, D.L. Porter, S.L. to fabrication artifacts not irradia- Hayes, M.K. Meyer, D.A. Petti, K. tion induced phases. These positivePasamehmetoglu, An approach to results justify the continuation offuel development and qualifica-ongoing High Flux Isotope Reactortion, J. Nucl. Mater. 371 (2007) (HFIR) irradiations of UN kernels232242. doi:10.1016/J.JNUC-and UN TRISO to higher burnups.MAT.2007.05.029.More generally this PIE shows how[2.] K.A. Terrani, N.A. Capps, M.J. Kerr, the MiniFuel design can be usedC.A. Back, A.T. Nelson, B.D. Wirth, for the rapid screening of novelS.L. Hayes, C.R. Stanek, Accelerat-fuel concepts. Because the Mini- ing Nuclear Fuel Development Fuel experiments are significantlyand Qualification: Engineering-different than traditional fueledScale Modeling and Simulation experiments, this PIE also servedIntegrated with Separate Ef-as a shakedown test of the PIEfects Testing, J. Nucl. Mater. 539 techniques that will be applied to(2020) 152267. doi:10.1016/j.future MiniFuel experiments. Thejnucmat.2020.152267.predicted temperatures for the fuel (approximately 500C) closely[3.] C.M. Petrie, J.R. Burns, A.M. matched the measured temperaturesRaftery, A.T. Nelson, K.A. Ter-(approximately 450C) derivedrani, Separate effects irradiation from temperature monitors (TM) intesting of miniature fuel speci-the capsules. The measured Burnupmens, J. Nucl. Mater. 526 (2019) in each capsule (5.2 to 8.9 MWd/ 151783. doi:10.1016/j.jnuc-kgU) was within 10% relative errormat.2019.151783.with the burnup predicted from neutronics simulations. Experimental evaluations of burnup and tempera-2020|AFC ACCOMPLISHMENTS 53'