2017 | AFC ACCOMPLISHMENTS 185 Project Description: The AFC irradiations are designed to explore the fuel performance of candidate transmutation and fast reactor fuel concepts in a simulated pseudo-fast neutron environment. The fast neutron environment is created using a cadmium filter while irradiating fuel in the AdvancedTest Reactor which is a thermal neutron spectrum materials test reactor.The proper temperature is achieved by a control gap between the test fuel cladding and a capsule that isolates the test specimen from the ATR primary coolant.The current set of tests under examination consist of a variety of alloys and forms that have shown some potential in out-of- reactor testing to enhance certain fuel performance properties.The potential for eliminating sodium bonding between the fuel alloy and cladding is also explored in these fuels. Spent sodium bonded fuel currently requires additional treatment prior to disposal which is undesirable. Out-of-reactor tests cannot fully capture all the impacts of irradiation, so these alloys and forms must be tested through irradiation. Successful candidate fuels will be carried forward for additional testing.The eventual goal is to test a fuel candidate that can out perform the historic standard fuel alloy (U-10Zr) and form and allow burnup beyond 20 atom percent and cladding temperatures in excess of 600°C. Additionally, exams continue on fuel concepts that include minor actinide (Np,Am) additions to well studied fuels. Understanding the effect minor actinides have on fuel performance (if any), may allow for the destruction of minor actinides in fast reactors which in turn would reduce the long term radiotoxicity of a geological repository. Accomplishments: Baseline PIE was completed on the 4 rodlets from AFC-4A.This test included some novel alloy compositions, an annular form, and a control solid U-10Zr rodlet.This test includes examination of the novel Molybdenum,Titanium, Zirconate alloy with and without Pd as an additive. Neutron radiography, gamma spectrometry, fission gas release, optical microscopy and chemical analysis is now complete on these pins, and they will be available for further exams if desired in the future. The AFC-4A microscopy samples were some of the first samples examined on the new optical microscope available at HFEF.This new microscope is capable of resolving micrometer scale features in fuel. In addition to