NSUF 25-5572: Environmental Cracking of High-Strength Materials
The objective of this work is to characterize the resistance of the material to environmental effects, as defined by the crack growth rate (CGR) as a function of the neutron dose. Samples of a precipitation-strengthened Ni alloy (X-750) with three different neutron doses are available in the NSUF library. Specimens for this work were part of a project at INL with EPRI to provide tensile, fracture toughness, and crack growth rate properties as a function of neutron dose for materials that are candidates for boiling water reactor (BWR) repairs [1].
Better experimental data and extended plant experience have eroded much of the “lore” in the industry surrounding immunity to EC and thresholds for crack initiation and growth [2]. Industry experts always point out the failure to see the connectedness of EC and the fundamental importance of plastic strain. Recent work by Chen et al [3] highlights the importance of crack tip strain rate and dK/dt to explain the dK/da accelerating effect in cold-worked Alloy 600. In this study, we introduce the plastic strain from neutron irradiation and the controlled loading rate to study its effect on the EC resistance.
This work focuses on rising K testing, as described in [4], to characterize the resistance to environmental cracking of high strength materials from a previous test program at INL [1]. The rising K testing proposed here is similar to the testing described in BWRVIP-84, Rev. 3 [5], but with significant modifications designed to differentiate SCC performance. All of the tests will use the same representative BWR environmental conditions (288°C) used in the recent INL testing [1]. In addition, the fastest loading rate used here (2 MPa√m / hr) is still considerably slower than that used in ref. [5].
Additional Info
| Field | Value |
|---|---|
| Awarded Institution | Nuclear Regulatory Commission |
| DOI | 10.46936/NSUF/60015726 |
| Embargo End Date | 2028-01-22 |
| Facility Tech Lead | Noé Morales |
| NSUF Call | FY 2025 Super RTE Call |
| PI | Patrick Purtscher |
| PIE Facilities | Fuels and Applied Science Building |
| Prep Facilities | Fuels and Applied Science Building |
| Project Member | Dr. Patrick Purtscher, MATERIALS ENGINEER - U.S. Nuclear Regulatory Commission (https://orcid.org/0009-0006-2334-8116) |
| Project Type | RTE |
| Sample Identifiers | 13211,13213,13215,13217,13261,13263,13415,13416,13419,13421,13423 |