An In-Situ Corrosion Small Punch Test for Developing Stress Corrosion Cracking in Stainless Steel

Area of Science:

• Nuclear Engineering
• Materials Science
• Corrosion Science

Background:

• Spent advanced gas-cooled reactor (AGR) fuel cladding is susceptible to stress corrosion cracking (SCC) during interim storage.
• SCC compromises the structural integrity of nuclear fuel storage systems.

Purpose of the Study:

• To develop and validate a novel small punch test (SPT) setup for studying SCC in fuel cladding.
• To minimize safety concerns associated with testing irradiated materials by using small sample volumes.

Main Methods:

• Accelerated SCC testing of 304 stainless steel surrogate material using the SPT setup.
• Circulation of a heated corrosive solution to induce SCC.
• Finite element modeling to analyze material mechanical behavior during testing.
• Characterization using scanning electron microscopy (SEM) and optical profilometry.

Main Results:

• The SPT setup successfully induced SCC and other corrosion behaviors in the surrogate material.
• Different corrosive environments were evaluated for their effects on material degradation.
• Mechanical behavior under test conditions was estimated via finite element analysis.

Conclusions:

• The developed SPT setup can rapidly induce SCC in small material samples.
• The methodology shows promise for evaluating irradiated fuel materials with further procedural enhancements.