NSUF 13-374: EFFECT OF RADIATION AND TEMPERATURE ON THE STABILITY OF OXIDE NANOCLUSTERS IN ODS STEEL
ODS ferritic steels exhibit relatively low swelling under radiation on account of their BCC ferritic structure, and high creep rupture strength at high temperature due to oxide nanoclusters composed of yttrium-oxide incorporated with titanium. The dispersed oxide nanoclusters impede dislocation climb and glide, enhance SIA-vacancy recombination, and perhaps act as sinks for helium, thereby limiting the helium reaching grain boundaries where it can have a detrimental on toughness. The stability of oxide nanoclusters at high temperatures in high dose environments is critical to the application of ODS steels for applications of components in a nuclear reactor, such as fuel cladding. ODS steels can be potential candidate for operations at 700oC and 200dpa. With the above background the proposed research will seek to understand the structural evolution in ODS steels by first implanting helium at 400kV at room temperature at the University of Michigan’s Ion Beam Laboratory. This will be followed by followed by irradiation with Ni+ ions from sub-zero to elevated temperatures at the Pacific Northwest National Laboratorys (PNNL) ion beam laboratory. Transmission electron microscopy (TEM) with energy dispersive spectroscopy (EDS) and High Resolution TEM (HRTEM) will be performed before and after irradiation to investigate the changes in size, density, composition, and crystallographic orientation of oxide nanoclusters greater than 5nm in size. For investigating and imaging such changes in nanoclusters less than 5nm in size, atom probe tomography (APT) will be used. Samples of irradiated ODS steels for APT and TEM analysis will be prepared using the focused ion beam (FIB) technique The proposed experimental effort is proposed as a 9 month program.
Additional Info
| Field | Value |
|---|---|
| Abstract | ODS ferritic steels exhibit relatively low swelling under radiation on account of their BCC ferritic structure, and high creep rupture strength at high temperature due to oxide nanoclusters composed of yttrium-oxide incorporated with titanium. The dispersed oxide nanoclusters impede dislocation climb and glide, enhance SIA-vacancy recombination, and perhaps act as sinks for helium, thereby limiting the helium reaching grain boundaries where it can have a detrimental on toughness. The stability of oxide nanoclusters at high temperatures in high dose environments is critical to the application of ODS steels for applications of components in a nuclear reactor, such as fuel cladding. ODS steels can be potential candidate for operations at 700oC and 200dpa. With the above background the proposed research will seek to understand the structural evolution in ODS steels by first implanting helium at 400kV at room temperature at the University of Michigan’s Ion Beam Laboratory. This will be followed by followed by irradiation with Ni+ ions from sub-zero to elevated temperatures at the Pacific Northwest National Laboratorys (PNNL) ion beam laboratory. Transmission electron microscopy (TEM) with energy dispersive spectroscopy (EDS) and High Resolution TEM (HRTEM) will be performed before and after irradiation to investigate the changes in size, density, composition, and crystallographic orientation of oxide nanoclusters greater than 5nm in size. For investigating and imaging such changes in nanoclusters less than 5nm in size, atom probe tomography (APT) will be used. Samples of irradiated ODS steels for APT and TEM analysis will be prepared using the focused ion beam (FIB) technique The proposed experimental effort is proposed as a 9 month program. |
| Award Announced Date | 2012-12-20T00:00:00 |
| Awarded Institution | None |
| Facility | None |
| Facility Tech Lead | Kevin Field |
| Irradiation Facility | None |
| PI | Kumar Sridharan |
| PI Email | [email protected] |
| Project Type | RTE |
| RTE Number | 374 |