2017 | AFC ACCOMPLISHMENTS 139 inserted in the glass mold prior to heat treatment and the other sample was heat treated while flat.After heat treating, both samples were a uniform dark color. Casting results showed pre- rolled samples performed better.The samples rolled post heat treatment did not hold the rolled shape as well as the post heat treatment rolled samples, and in some cases, the foil was inte- rior to the fuel.While the 25 µm foil continued to behave poorly, the 50 µm foil rolled pre-heat treatment appeared to better maintain integrity and shape through the casting process.Although some minor infiltration and evidence of interaction was also observed, its overall performance was improved. Figure 2 shows an example of the minor infiltration, and an overall view of the fuel. The final round of experiments used a slurry coating of ZrO2 on the interior surface of the 50 µm foil after heat treatment to further mitigate interactions and to possible seal any openings for infiltration. Casting and heat treatments were performed in a similar manner to previous tests. The resulting castings showed a gap between the fuel foil wrap. Figure 3 shows a cross section of the final pin. This was the desired result to ensure the foil would not bond to the fuel and not be able to unwrap during irradiation.Therefore, this preparation technique with the 50 µm foil was identified as the preferred method for fabrication via arc-melting, and was shown to be capable of producing the desired results. Figure 3. Heat treated 50 µm foil with ZrO2 coating. SEM image (Top) shows area highlighted in left image. Notice no discernable infiltration.