Tritium embrittlement of austenitic stainless-steel tubing at low helium contents

Journal Article · Thu Jul 01 00:00:00 EDT 2021 · Fusion Engineering and Design

DOI:https://doi.org/10.1016/j.fusengdes.2021.112413· OSTI ID:1772033

Krentz, Timothy M. ^[1]; Ronevich, Joseph A. ^[2]; Balch, Dorian K. ^[2]; Marchi, Chris San ^[2]

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1. Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL)
2. Sandia National Lab. (SNL-CA), Livermore, CA (United States)

Austenitic stainless steels are the standard materials for containment of hydrogen and tritium because of their resistance to mechanical property degradation in those environments. The mechanical performance of the primary containment material is critical for tritium handling, processing, and storage, thus comprehensive understanding of the processes of tritium embrittlement is an enabling capability for fusion energy. This work describes the investigation of the effects of low levels of tritium-decay-helium ingrowth on 304 L tubes. Long-term aging with tritium leads to high helium contents in austenitic stainless steels and can reduce fracture toughness by 95 %, but the details of behavior at low helium contents are not as well characterized. Here, we present results from tensile testing of tritium pre-charged 304 L tube specimens with a variety of starting microstructures that all contain a low level of helium. The results of the tritium exposed-and-aged materials are compared to previously reported results on similar specimens tested in an unexposed condition as well as the hydrogen precharged condition. Tritium precharging and aging for a short duration resulted in increased yield strengths, ultimate tensile strengths and slightly increased elongation to failure, comparable to higher concentrations of hydrogen precharging.

• Research Organization: Sandia National Laboratories (SNL-CA), Livermore, CA (United States); Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL)
• Sponsoring Organization: USDOE National Nuclear Security Administration (NNSA)
• Grant/Contract Number: AC04-94AL85000; AC09-08SR22470; NA0003525
• OSTI ID: 1772033
• Alternate ID(s): OSTI ID: 1833154; OSTI ID: 1776684; OSTI ID: 1782273; OSTI ID: 23194846
• Report Number(s): SAND--2021-2863J; SRNL-STI--2020-00545; 694691
• Journal Information: Fusion Engineering and Design, Journal Name: Fusion Engineering and Design Vol. 168; ISSN 0920-3796
• Publisher: Elsevier
• Country of Publication: United States
• Language: English

Related Subjects

70 PLASMA PHYSICS AND FUSION TECHNOLOGY
Austenitic stainless steel
Embrittlement
Hydrogen
Tritium