The paper "Transformation mechanisms and governing orientation relationships through selective dissolution of Ni via liquid metal dealloying from (FeCo)xNi100−x precursors" has been published at Materials & Design.
Liquid metal dealloying (LMD) is a promising technique that can be used to synthesize non-noble porous materials by preventing oxidation through using a metallic melt. However, the phase transformation behavior between a parent grain and synthesized ligaments surrounded by penetrating liquid metal channels remains unknown, despite its importance on the final physical properties. In this study, the temperature effect on the transformation mechanisms during the LMD process is investigated. At a low temperature of 600 °C, a fcc grain of (FeCo)xNi100−x precursors transforms to bcc FeCo ligaments by following unique orientation relationships (ORs), which differ from the well-known ORs like Bain, Kurdjumov-Sachs and Nishiyama-Wassermann. A few select variants are generated in the proposed ORs, and the formation of coincident site lattice boundaries is shown to play a crucial role in the variant selection to reduce the internal energy of the initial nanostructure. However, at a higher temperature of 800 °C, the crystal orientation of ligaments prefers to align in the <111> direction, which is parallel to the flow direction of Mg melt, owing to a strong interaction between the melt and ligaments. Ligaments are elongated along with the fiber texture, and this transformation behavior is irrelevant to the parent orientation.
Highlights
• Governing orientation relationships during liquid metal dealloying were revealed.
• Transformation mechanism varied depending on the dealloying temperature.
• At 600 °C, the suggested ORs are rotated by 35.3°, 40.5°, and 45.1° from the KS OR.
• Only a few variants were transformed from one parent fcc grain to bcc ligaments.
• The formation of CSL boundaries play a crucial role in the variant selection.