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arXiv · 1708.06801

Ice-Templated W-Cu Composites with High Anisotropy

André Röthlisberger·Sandra Häberli·Henning Galinski·David C. Dunand·Ralph Spolenak
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Abstract

Controlling anisotropy in self-assembled structures enables engineering of materials with highly directional response. Here, we harness the anisotropic growth of ice walls in a thermal gradient to assemble an anisotropic refractory metal structure, which is then infiltrated with Cu to make a composite. Using experiments and simulations, we demonstrate on the specific example of tungsten-copper composites the effect of anisotropy on the electrical and mechanical properties. The results are compared to isotropic tungsten-copper composites fabricated by standard powder metallurgical methods. Our results have the potential to fuel the development of more efficient materials, used in electrical power grids and solar-thermal energy conversion systems. The method presented here can be used with a variety of refractory metals and ceramics, which fosters the opportunity to design and functionalize a vast class of new anisotropic load-bearing hybrid metal composites with highly directional properties.

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André Röthlisberger, Sandra Häberli, Henning Galinski, David C. Dunand, Ralph Spolenak. 2017-08-22. Ice-Templated W-Cu Composites with High Anisotropy. https://doi.org/10.1038/s41598-018-36604-9

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