Assessment of Post-Irradiation Examination Techniques for Advanced Reactor Fuel and Materials


Book Description

This publication has been developed based on the results of the Technical Meeting on Advances in Post-Irradiation Examination Techniques for Power-Reactor Irradiated Fuels and Innovative Fuels held in July 2021. It explores the use of existing and new post-irradiation examination (PIE) techniques for the study of next-generation fuel types. Specifically, this publication provides an overall understanding of what important performance parameters are typically studied for each fuel type to properly assess its performance, and what are the relevant PIE techniques required for the analyses. Its intended audience comprises nuclear fuel designers, manufacturers, operators, regulators, academia and policy makers who work with the nuclear fuel community




Post-irradiation Examination Techniques for Research Reactor Fuels


Book Description

Post-irradiation examination (PIE) is an indispensable step in the selection of new or improved research reactor fuel, and in the characterization and understanding of its in-core behaviour. This publication provides an introduction to PIE techniques. It describes a typical PIE process from intercycle inspections in the reactor pool or channel, to hot cell PIE, which is subdivided into non-destructive and destructive testing techniques with their typical output, advantages and drawbacks, and their applicability to understanding fuel irradiation behaviour. Much of the work presented in this publication originated from the research and development of new low enriched uranium research reactor fuels. Intended readers include research reactor operators, regulators and their technical support organizations, fuel developers and manufacturers, laboratory staff, and policy makers.




National Postirradiation Examination Workshop Report


Book Description

A National Post-Irradiation-Examination (PIE) Workshop was held March 29-30, 2011, in Washington D.C., stimulated by the DOE Acting Assistant Secretary for Nuclear Energy approval on January 31, 2011 of the "Mission Need Statement for Advanced Post-Irradiation Examination Capability". As stated in the Mission Need, "A better understanding of nuclear fuels and material performance in the nuclear environment, at the nanoscale and lower, is critical to the development of innovative fuels and materials required for tomorrow's nuclear energy systems." (2011) Developing an advanced post-irradiation capability is the most important thing we can do to advance nuclear energy as an option to meeting national energy goals. Understanding the behavior of fuels and materials in a nuclear reactor irradiation environment is the limiting factor in nuclear plant safety, longevity, efficiency, and economics. The National PIE Workshop is part of fulfilling or addressing Department of Energy (DOE) missions in safe and publically acceptable nuclear energy. Several presentations were given during the opening of the workshop. Generally speaking, these presentations established that we cannot continue to rely on others in the world to provide the capabilities we need to move forward with nuclear energy technology. These presentations also generally identified the need for increased microstructural understanding of fuels and materials to be coupled with modeling and simulation, and increased accessibility and infrastructure to facilitate the interaction between national laboratories and participating organizations. The overall results of the work of the presenters and panels was distilled into four primary needs 1. Understanding material changes in the extreme nuclear environment at the nanoscale. Nanoscale studies have significant importance due to the mechanisms that cause materials to degrade, which actually occur on the nanoscale. 2. Enabling additional proficiency in experimentation and analysis through robust modeling coupled with advanced characterization. 3. Advancing the infrastructure and accessibility of physical and administrative systems needed to meet the needs of participating organizations that are subject to different time cycles and constraints that make working and collaborating the national laboratories challenging. 4. Pursuing in-situ analysis and instrumentation to support the examination of dynamic changes to materials' microstructure, deformation, and surface effects as they occur with time scales rather than the static comparison offered by current PIE methods. This Workshop Report responds to the research challenges for advanced/future PIE needs for nuclear materials development outlined by Energy Secretary Chu and the DOE-NE Research and Development Roadmap report, which was delivered to Congress in April 2010, (DOE-NE, 2010) by identifying the technial needs for fuel and material development specifically related to PIE. The information from the panels address these research challenges by identifying specific needs related to each of the topical areas. The focus of the Workshop was to identify gaps in the enabling capabilities for nuclear energy research and to identify high-priority fundamental capabilities to enable research to be completed that would likely have high impact on enabling nuclear energy as a significant contributor to energy production portfolios.




Post-Irradiation Examination Techniques for Research Reactor Fuels


Book Description

Post-irradiation examination (PIE) is an indispensable step in the selection of new or improved research reactor fuel, and in the characterization and understanding of its in-core behaviour. This publication provides an introduction to PIE techniques. It describes a typical PIE process from intercycle inspections in the reactor pool or channel, to hot cell PIE, which is subdivided into non-destructive and destructive testing techniques with their typical output, advantages and drawbacks, and their applicability to understanding fuel irradiation behaviour. Much of the work presented in this publication originated from the research and development of new low enriched uranium research reactor fuels. Intended readers include research reactor operators, regulators and their technical support organizations, fuel developers and manufacturers, laboratory staff, and policy makers.




National Postirradiation Examination Workshop Needs Assessment


Book Description

The development of nuclear fuels and materials requires a clear understanding of irradiation effects on the materials performance. Development of this understanding at present relies on irradiation experiments ranging from tests aimed at targeted phenomenology to integral effects under both prototypic and off-normal conditions. Within the new DOE paradigm of a science-based approach aimed at more fundamental understanding of fuel performance, more specialized experiments and measurements are needed. To support the development of such fuels and materials, especially under a science-based development strategy, the nation needs a consolidated, state-of-the-art, post-irradiation examination (PIE) capability that can reliably extract the needed data from the experimental programs. In some cases, new capabilities beyond the current state-of-the art need to be developed and implemented to perform measurements that were not needed in the more empirically based approaches used in earlier fuel development and qualification programs. A national PIE workshop was held in March 2011 which solicited the PIE needs that are necessary to support both DOE and U.S. goals for nuclear energy. These needs recognize that significant capability already exists that must be maintained, upgraded and continued while bringing online new capabilities that support research on highly irradiated fuels and materials. Further, these needs mostly focus on the reducing the time and length scales in which materials can be examined and coupling these measurements with a robust modeling capability within an infrastructure that can meet the needs of higher demand and a variety of customers. A consolidated capability where a comprehensive set of measurements can be simultaneously performed is essential for efficiently implementing fuel and materials development programs in a cost effective manner. This document captures the national PIE needs necessary to support current and future research, and where possible identifies where those capabilities are allocated.




Analysis of Options and Experimental Examination of Fuels for Water Cooled Reactors with Increased Accident Tolerance (Actof)


Book Description

There is high interest in new fuel types with increased accident tolerance. These range from using an oxidation resistant coating on zirconium based cladding to alternate fuel and cladding materials. These new fuels/claddings under development must be licensed before being deployed industrially and therefore research is being undertaken to assess their behaviour in various conditions. This publication arises from an IAEA coordinated research project (CRP) dealing with the acquisition of data through experiments on new fuel types and cladding materials and the development of modelling capacity to predict the behaviour of the components and the integral performance of accident tolerant fuel designs under normal and transient conditions. Demonstrations of improvements under severe accident conditions were documented. Several coated cladding materials were produced, tested, characterized and analysed in round robin tests carried out within the CRP. For improvement and validation of fuel performance codes, several benchmarks were organized to compare and analyse predictions of the extended codes. The findings and conclusions of the CRP are summarized in this publication.










Post-irradiation Examination and Fission Product Inventory Analysis of AGR-1 Irradiation Capsules


Book Description

The AGR-1 experiment was the first in a series of Advanced Gas Reactor (AGR) experiments designed to test TRISO fuel under High Temperature Gas Reactor irradiation conditions. This experiment was irradiated in the Advanced Test Reactor (ATR) at Idaho National Laboratory (INL) and is currently undergoing post-irradiation examination (PIE) at INL's Materials and Fuels Complex (MFC). The inventory and distribution of fission products, especially Ag-110m, was assessed and analyzed for all the components of the AGR-1 capsules. This data should help inform the study of fission product migration in coated particle fuel. Gamma spectrometry was used to measure the activity of various different fission products in the different components of the AGR-1 test train. Each capsule contained: 12 fuel compacts, a graphite holder that kept the fuel compacts in place, graphite spacers that were above and below the graphite holders and fuel compacts, gas lines through which a helium neon gas mixture flowed in and out of each capsule, and the stainless steel shell that contained the experiment. Gamma spectrometry results and the experimental techniques used to capture these results will be presented for all the capsule components. The components were assayed to determine the total activity of different fission products present in or on them. These totals are compared to the total expected activity of a particular fission product in the capsule based on predictions from physics simulation. Based on this metric, a significant fraction of the Ag-110m was detected outside the fuel compacts, but the amount varied highly between the 6 capsules. Very small fractions of Cs-137 (




Guidebook on Destructive Examination of Water Reactor Fuel


Book Description

This guidebook gives a complete survey of destructive techniques available to perform microstructural examinations, elemental and isotopic analyses and measurement of physical, chemical and mechanical properties of irradiated fuel and structural materials, and describes asociated refabrication and instrumentation techniques. Non-destructive examination (NDE) data are verified by destructive examination (DE) data. The data were submitted to the IAEA by hot laboratories from 12 countries and one international organization (CEC/ITU) during the period 1992-1995. Together with IAEA Technical Reports Series No.322 (1991), Guidebook on non-destructive examination of water reactor fuel, it presents the most comprehensive summary of post-irradiation examination techniques to date.