Abstract
Plans for extended operation of US nuclear power plants (NPPs) beyond 60 years have resulted in a renewed focus on the long-term aging of materials in NPPs, and specifically on reactor cavity concrete. To better understand the effects of neutron irradiation on reactor cavity concrete, a select group of mineral analogues of concrete aggregates were irradiated at the Oak Ridge National Laboratory High Flux Isotope Reactor at three different fluence levels and at two temperatures. The purpose was to investigate the degradation of mechanical properties at neutron doses above the levels expected in US NPPs under extended operation. Preliminary findings using nanoindentation clearly show that changes in the mechanical properties of these minerals can be observed and correlated to the neutron-induced damage. Scanning electron microscopy reveals changes in deformation and fracture mechanisms in the irradiated mineral analogies. Results for the nanohardness as a function of dose and temperature are presented and discussed for quartz, calcite, and dolomite.
| Original language | English |
|---|---|
| Title of host publication | Minerals, Metals and Materials Series |
| Publisher | Springer International Publishing |
| Pages | 1367-1377 |
| Number of pages | 11 |
| ISBN (Print) | 9783030046385, 9783030046392, 9783319515403, 9783319651354, 9783319728520, 9783319950211 |
| DOIs | |
| State | Published - 2019 |
| Event | 18th International Conference on Environmental Degradation of Materials in Nuclear Power Systems – Water Reactors 2019 - Boston, United States Duration: Aug 18 2019 → Aug 22 2019 |
Publication series
| Name | Minerals, Metals and Materials Series |
|---|---|
| ISSN (Print) | 2367-1181 |
| ISSN (Electronic) | 2367-1696 |
Conference
| Conference | 18th International Conference on Environmental Degradation of Materials in Nuclear Power Systems – Water Reactors 2019 |
|---|---|
| Country/Territory | United States |
| City | Boston |
| Period | 08/18/19 → 08/22/19 |
Funding
This manuscript has been authored by UT-Battelle, LLC, under Contract No. DE-AC0500OR22725, with the U.S. Department of Energy. The United States Government retains and the publisher, by accepting the article for publication, acknowledges that the United States Government retains a non-exclusive, paid-up, irrevocable, worldwide license to publish or reproduce the published form of this manuscript, or allow others to do so, for the United States Government purposes. The Department of Energy will provide public access to these results of federally sponsored research in accordance with the DOE Public Access Plan ( http://energy.gov/downloads/doe-public-access-plan ). Extending the operating lifetimes of current nuclear power plants (NPPs) beyond 60 years and making additional improvements in their productivity is essential to meeting future US national energy needs. Although much of the early research has focused on the performance and possible degradation mechanisms of metals affected by increased periods of exposure to time to temperatures, stresses, coolants, and radiation fields, other materials, such as concrete are also critical to the long-term NPP operation. To address these extended lifetimes effects, Oak Ridge National Laboratory (ORNL), through the support of the US Department of Energy (DOE), Light Water Reactor Sustainability (LWRS) Program, has established a research plan to investigate the aging and degradation processes associated with concrete Concrete degradation used in NPPs [, ]. The basis for the plan arose in part from the Expanded Materials Degradation Analysis (EMDA) report on “The Aging of Concrete and Civil Structures”, an effort jointly supported by DOE and the US Nuclear Regulatory Commission and performed by expert panels from US national laboratories, industry, academia, and international organizations. A key finding of the panel of experts on concrete was that there is an urgent need to develop a consistent knowledge base on radiation damage in reactor cavity concrete []. This research was sponsored by the US Department of Energy, Office of Nuclear Energy, LWRS Program. The authors gratefully acknowledge that the irradiation of the mineral analogues of concrete aggregates was conducted at the HFIR, a DOE Office of Science User Facility operated by ORNL. The authors wish to thank Dr. Keith Leonard for his support and Tom Geer for his guidance on polishing the mineral analogue samples.
| Funders | Funder number |
|---|---|
| Light Water Reactor Sustainability | |
| US national laboratories | |
| U.S. Department of Energy | |
| U.S. Nuclear Regulatory Commission | |
| Office of Nuclear Energy | |
| Oak Ridge National Laboratory |
Keywords
- Aggregates
- Concrete degradation
- Mineral analogues
- Nanohardness
- Neutron irradiation