NSUF 22-4392: Atom probe characterization of oxide and metal/oxide interface on proton irradiated Zry-4 after exposure in high-temperature water
The irradiation induced microchemistry evolution was proposed to be one of the leading causes of the observed in-reactor accelerated corrosion kinetics of Zry-4 alloy at higher burnups. Although there are ample microstructural analyses of the resulting in-reactor grown oxides, there has not been a systematic study to reveal the individual effect of radiation damage, water radiolysis, and active radiation on oxide growth kinetics and oxide chemistry. This proposal is aimed at using atom probe tomography (APT) to study the microchemistry of proton irradiated Zircaloy-4 alloys after various high-temperature in-situ or ex-situ aqueous exposures. The main hypothesis tested is that the irradiation induced microstructure and microchemistry changes in the matrix and precipitation are responsible for the accelerated corrosion rate at high burnups in reactor irradiated Zircaloy-4. Our recent publication on proton irradiated samples has already partially proved this hypothesis. The next step is to examine whether proton irradiated samples behave similarly to neutron irradiated samples during corrosion tests in simulated reactor conditions. The primary research objective of this study is to provide knowledge on microchemistry evolution influenced by the proton irradiation, including alloying elements redistribution, clustering, segregation at microstructural features on either metal matrix, metal/oxide interfaces, or in the resulting oxide. This study will utilize the FIB and APT facility in the Microscopy and Characterization Suite (MaCS) at the Center for Advanced Energy Studies (CAES) to fabricate and analyze the APT needles of proton irradiated and corroded Zry-4 samples. The sample contains both metallic and oxide regions, it is essential to capture both regions on one needle. The APT analysis will be performed under laser mode to generate a higher atomic yield. Since Zr APT needles are very easy to fracture during APT analysis, more APT needles would ensure a greater success rate and have higher quality datasets (>10 million atoms). In total, we are requesting six days of FIB at MaCS and ten days of APT at CAES instrument time to finish this RTE. IVAS software will be used to analyze the structural and compositional information in the 3D reconstructed APT needle. Since nanoclusters are expected to be present in the analyzed volume, iso-surface and maximum separation methods will be applied to identify the nanoclusters. A proximity histogram will be used to analyze the chemistry of nanoclusters.
Additional Info
| Field | Value |
|---|---|
| Abstract | The irradiation induced microchemistry evolution was proposed to be one of the leading causes of the observed in-reactor accelerated corrosion kinetics of Zry-4 alloy at higher burnups. Although there are ample microstructural analyses of the resulting in-reactor grown oxides, there has not been a systematic study to reveal the individual effect of radiation damage, water radiolysis, and active radiation on oxide growth kinetics and oxide chemistry. This proposal is aimed at using atom probe tomography (APT) to study the microchemistry of proton irradiated Zircaloy-4 alloys after various high-temperature in-situ or ex-situ aqueous exposures. The main hypothesis tested is that the irradiation induced microstructure and microchemistry changes in the matrix and precipitation are responsible for the accelerated corrosion rate at high burnups in reactor irradiated Zircaloy-4. Our recent publication on proton irradiated samples has already partially proved this hypothesis. The next step is to examine whether proton irradiated samples behave similarly to neutron irradiated samples during corrosion tests in simulated reactor conditions. The primary research objective of this study is to provide knowledge on microchemistry evolution influenced by the proton irradiation, including alloying elements redistribution, clustering, segregation at microstructural features on either metal matrix, metal/oxide interfaces, or in the resulting oxide. This study will utilize the FIB and APT facility in the Microscopy and Characterization Suite (MaCS) at the Center for Advanced Energy Studies (CAES) to fabricate and analyze the APT needles of proton irradiated and corroded Zry-4 samples. The sample contains both metallic and oxide regions, it is essential to capture both regions on one needle. The APT analysis will be performed under laser mode to generate a higher atomic yield. Since Zr APT needles are very easy to fracture during APT analysis, more APT needles would ensure a greater success rate and have higher quality datasets (>10 million atoms). In total, we are requesting six days of FIB at MaCS and ten days of APT at CAES instrument time to finish this RTE. IVAS software will be used to analyze the structural and compositional information in the 3D reconstructed APT needle. Since nanoclusters are expected to be present in the analyzed volume, iso-surface and maximum separation methods will be applied to identify the nanoclusters. A proximity histogram will be used to analyze the chemistry of nanoclusters. |
| Award Announced Date | 2022-06-14T07:31:22.803 |
| Awarded Institution | None |
| Facility | None |
| Facility Tech Lead | Yaqiao Wu |
| Irradiation Facility | None |
| PI | Peng Wang |
| PI Email | [email protected] |
| Project Type | RTE |
| RTE Number | 4392 |