|About this Abstract
||Materials Science & Technology 2020
||Advanced Characterization of Materials for Nuclear, Radiation, and Extreme Environments
||Effects of Post-Processing Variability on Radiation Response of Additively-Manufactured HT9
||Pengyuan Xiu, Niyanth Sridharan, Kevin Field
|On-Site Speaker (Planned)
In this study, the radiation response of an additively manufactured (AM) HT9 alloy using laser powder blown directed energy deposition (DED) was studied. Three HT9 variants were investigated, one directly after DED (as-built, or ASB) and two post-build heat-treated following DED (called ACO3 and FCRD). The unirradiated microstructures varied significantly with the ASB specimen being highly defective (≥1014/m2 estimated) while the ACO3 and FCRD alloys exhibited dislocation densities of 2.26×1014/m2 and 3.58×1014/m2 respectively. The variants were dual-ion irradiated to the damage level of 16.6 dpa and 4 He appm/dpa at 445°C to study the radiation response. Radiation induced cavity densities were 3.1×1022/m2, 7.0×1021/m2, and 4.9×1021/m2, with the size of 4.3±1.7nm, 6.4±6.7nm, and 4.3±2.5nm for ASB, ACO3 and FCRD respectively. Nanometric Ni/Si-rich clusters existed only in the ACO3 and FCRD variants with densities around 8×1021/m2 after irradiation. The implications of the AM-based sink strengths on the radiation tolerance will be discussed.
||Planned: Publication outside of MS&T