In an article published very recently in the journal Small, we investigate the origins of certain eutectics that grow into spiral geometry. The spiral formation follows a two‐step process, wherein the first step is mediated by the low solid–liquid interfacial energy of a precursor phase, and the second step by crystallographic defects on the precursor. The cover at right features a computed X‐ray nano‐tomography image of spiral eutectics in Mg‐Zn alloy showing multiple spiral eutectic colonies with the eutectic MgZn2 and Zn phases shown in dark and light false colors (image courtesy of H. Bale). Way to go Saman, Yeqing, and coworkers!
'“As molten metal alloys cool, solid structures begin to form internally as small atomic clusters crystallize. By fine-tuning the cooling conditions, researchers can steer these crystallization mechanisms to produce a range of different structures in solid materials. Particularly intriguing structures can arise through non-equilibrium cooling – including “spiral eutectics”, which arise in mixtures of two or more solid metal phases. These materials can spontaneously self-arrange themselves into spirals resembling a DNA helix …”
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