b'Figure 3. TEM micrographs of voidsdefects was suppressed, and it wasenced lower void density overall and in Cr 18 Fe 27 Mn 27 Ni 28 , Cr 15 Fe 35 Mn 15 Ni 35 ,revealed by quantification of defectmore variation in void size, especially and 316H stainless steel irradiated toclusters that in body centered cubicwith depth. See Figure 3.150 dpa at 500 C using 4.0 MeV Ni heavy ions (BCC) and face centered cubic (FCC) The first high-throughput irradiation HEAs, the primary defect produc- of an as-deposited magnetron-sput-tion is reduced compared to lesstered combinatorial CrFeMnNi thin compositionally complex materialsfilm to 5 dpa at room temperature (see Figure 2). High-temperaturewas performed at the UW-Madison irradiations revealed a difference inIon Beam Laboratory (IBL) using 4 the size of faulted dislocation loopsMeV Ni heavy ions. The develop-A compositionallyin Cr18Fe27Mn27Ni28 and Cr15F- ment of the automated 2D irradia-complex base matrixe35Mn15Ni35 alloys after 2 dpa,tion stage at the UW IBL was led by may delay thewhich was attributed to the effect ofMichael Moorehead and Dr. Benoit nucleation stage andcomposition on vacancy mobility,Queylat. Likely because the as-extend the incubationstacking fault energy, and nucleationdeposited thin film has nano-grains, time of irradiation- of interstitial loops.no voids formed, and energy dis-induced extended Bulk heavy ion irradiations of Cr18F- persive spectroscopy (EDS) revealed defects such as voidse27Mn27Ni28, Cr15Fe35Mn15Ni35,no significant elemental redistribu-and dislocation loopsand 316H stainless steel were per- tion. Most points on the thin film and may be used as aformed to 150 dpa at 500 C and 600remained stable on the substrate design parameter toC and voids were characterized usingduring irradiation, setting up the next tune alloys for radiationTransmission Electron Microscopystep, which is to irradiate an annealed damage resistance in(TEM). The swelling measurementswafer with a reduced sink density addition to the classicalfrom these experiments are used to(i.e., larger grain size) to better probe sink strength densityconstruct temperature-swelling andthe role of the compositionally com-approach. local dpa-swelling curves to compareplex matrix on irradiation resistance. void swelling across materials (HEAs HEA, which began homogeneous vs 316HSS) Early characterizationand single-phase, were characterized indicates that while 316HSS experi- for irradiation-induced chemical enced relatively uniform void swellingredistribution using Super-X EDS near across the irradiation depth, voidvoids and along depth profile as part populations in the two HEAs experi-106 2021|AFC ACCOMPLISHMENTS'