Radiation-induced segregation on defect clusters in single-phase concentrated solid-solution alloys

Journal Article · Sat Apr 01 00:00:00 EDT 2017 · Acta Materialia

DOI:https://doi.org/10.1016/j.actamat.2017.01.019· OSTI ID:1393687

Lu, Chenyang; Yang, Taini; Jin, Ke; Gao, Ning; Xiu, Pengyuan; Zhang, Yanwen; Gao, Fei; Bei, Hongbin; Weber, William J.; Sun, Kai; Dong, Yan; Wang, Lumin

A group of single-phase concentrated solid-solution alloys (SP-CSAs), including NiFe, NiCoFe, NiCoFeCr, as well as a high entropy alloy NiCoFeCrMn, was irradiated with 3 MeV Ni²⁺ ions at 773 K to a fluence of 5 10¹⁶ ions/cm² for the study of radiation response with increasing compositional complexity. Advanced transmission electron microscopy (TEM) with electron energy loss spectroscopy (EELS) was used to characterize the dislocation loop distribution and radiation-induced segregation (RIS) on defect clusters in the SP-CSAs. The results show that a higher fraction of faulted loops exists in the more compositionally complex alloys, which indicate that increasing compositional complexity can extend the incubation period and delay loop growth. The RIS behaviors of each element in the SP-CSAs were observed as follows: Ni and Co tend to enrich, but Cr, Fe and Mn prefer to deplete near the defect clusters. RIS level can be significantly suppressed by increasing compositional complexity due to the sluggish atom diffusion. According to molecular static (MS) simulations, disk like segregations may form near the faulted dislocation loops in the SP-CSAs. Segregated elements tend to distribute around the whole faulted loop as a disk rather than only around the edge of the loop.

• Research Organization: Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Energy Frontier Research Centers (EFRC) (United States). Energy Dissipation to Defect Evolution (EDDE)
• Sponsoring Organization: USDOE Office of Science (SC), Basic Energy Sciences (BES)
• Grant/Contract Number: AC05-00OR22725
• OSTI ID: 1393687
• Alternate ID(s): OSTI ID: 1361347
• Journal Information: Acta Materialia, Journal Name: Acta Materialia Vol. 127 Journal Issue: C; ISSN 1359-6454
• Publisher: Elsevier
• Country of Publication: United States
• Language: English

Related Subjects

38 RADIATION CHEMISTRY, RADIOCHEMISTRY, AND NUCLEAR CHEMISTRY
Radiation induced segregation
Single- phase concentrated solid-solution alloys
High-entropy alloys
Electron energy loss spectroscopy
Molecular static simulations