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arXiv · 2605.25834

Dealloying by peritectic melting

Mingwang Zhong·Alain Karma
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Abstract

Peritectic melting of Ti--Ag has been shown experimentally to form bicontinuous structures, but the mechanism remains unclear. Here we use phase-field simulations to show that these structures arise from a morphological instability of liquid film migration in three dimensions: a Ti-rich solid growing through an Ag-rich liquid film develops a branched seaweed or dendritic structure whose side branches coalesce to form handles, generating a high-genus bicontinuous topology. A sharp-interface theory predicts a solidification-front velocity and an initial ligament width that are constant in time, in contrast to liquid metal dealloying; subsequent $t^{1/3}$ coarsening reproduces the experimentally observed final ligament width.

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Mingwang Zhong, Alain Karma. 2026-05-25. Dealloying by peritectic melting. https://arxiv.org/abs/2605.25834

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