Nanoindentation Test of Ion-Irradiated Materials: Issues, Modeling and Challenges

Area of Science:

• Materials Science
• Nuclear Engineering
• Mechanical Engineering

Background:

• Neutron irradiation increases yield strength and decreases ductility in metals.
• Irradiation hardening impacts fracture toughness and ductile-to-brittle transition temperature (DBTT) in body-centered cubic (bcc) alloys.
• Ion irradiation is crucial for studying radiation effects in nuclear materials.

Purpose of the Study:

• To review challenges in nanoindentation analysis of ion-irradiated materials.
• To discuss methods for addressing surface morphology and mechanical property changes.
• To explore modeling approaches and future directions for nanoindentation testing.

Main Methods:

• Review of nanoindentation techniques for ion-irradiated materials.
• Analysis of surface effects (roughness, contamination, pile-up, indentation size effect).
• Review of crystal plasticity finite element method (CPFEM) modeling.

Main Results:

• Nanoindentation is key for characterizing mechanical changes in shallow ion-irradiated layers.
• Surface morphology and mechanical property variations complicate nanoindentation analysis.
• Modeling and high-temperature testing present significant challenges.

Conclusions:

• Addressing nanoindentation complexities is vital for accurate irradiation hardening assessment.
• Further research is needed for high-temperature and multiscale nanoindentation simulations.
• This review provides insights into material characterization for nuclear applications.