Work

Resolving solidification-derived heterogeneities in a martensitic stainless steel by large-volume PFIB tomography

Year: 2026

Type: article

Abstract: Large-volume PFIB-based 3D-EBSD/SEM tomography was used to resolve solidification-derived heterogeneities in a CA6NM martensitic steel. δ-ferrite particles, inclusions, and micropores were reconstructed in 3D, revealing distinct morphologies and spatial distributions. δ-ferrite morphology depends on proximity to prior-austenite grain boundaries, with boundary-attached particles remaining elongated and faceted, whereas particles within grain interiors evolve into small, spheroidal remnants. Micropores were classified into gas, gas-shrinkage, and shrinkage pores, while inclusions were uniformly small and near-spherical. Spatial analysis shows strong clustering of micropores relative to the more uniform distribution of δ-ferrite, highlighting the capability of PFIB-based 3D characterization to quantify solidification-derived heterogeneities in martensitic steels. • Large-volume PFIB tomography enables 3D analysis of casting heterogeneities. • δ-ferrite morphology varies from faceted boundary particles to spheroidal interiors. • 3D morphology distinguishes gas, gas-shrinkage, and shrinkage pores. • Spatial statistics reveal distinct clustering behaviors of defects.

Source: Materials Letters

DOI: 10.1016/j.matlet.2026.140178

Authors: Mehdi Mosayebi, Daniel Paquet, Pierre-Antony Deschênes, Laurent Tôn-Thât, Nabil Bassim

Institutions: Canadian Centre for Electron Microscopy, McMaster University, Hydro-Québec

Language: English

Topic: Advanced Materials Characterization Techniques

Subfield: Biomedical Engineering

Field: Engineering

Domain: Physical Sciences

Open Access status: hybrid

Estimated APC paid: $2,870

Funders: Mitacs, Natural Sciences and Engineering Research Council of Canada