On‐Demand Programming of Liquid Metal‐Composite Microstructures through Direct Ink Write 3D Printing

Abstract

Soft, elastically deformable composites with liquid metal (LM) droplets can enable new generations of soft electronics, robotics, and reconfigurable structures. However, techniques to control local composite microstructure, which ultimately governs material properties and performance, is lacking. Here a direct ink writing technique is developed to program the LM microstructure (i.e., shape, orientation, and connectivity) on demand throughout elastomer composites. In contrast to inks with rigid particles that have fixed shape and size, it is shown that emulsion inks with LM fillers enable in situ control of microstructure. This enables filaments, films, and 3D structures with unique LM microstructures that are generated on demand and locked in during printing. This includes smooth and discrete transitions from spherical to needle‐like droplets, curvilinear microstructures, geometrically complex embedded inclusion patterns, and connected LM networks. The printed materials are soft (modulus 600 % strain), and can be made locally insulating or electrically conductive using a single ink by controlling the process conditions. These capabilities are demonstrated by embedding elongated LM droplets in a soft heat sink, which rapidly dissipates heat from high‐power LEDs. These programmable microstructures can enable new composite paradigms for emerging technologies that demand mechanical compliance with multifunctional response.

Document Details

Document Type
Pub Defense Publication
Publication Date
Apr 17, 2022
Source ID
10.1002/adma.202200182

Entities

People

  • Aaron Haake
  • Eric J Markvicka
  • Gwyneth M. Schloer
  • Michael D. Bartlett
  • Ravi Tutika

Organizations

  • Defense Advanced Research Projects Agency
  • National Science Foundation Directorate for Engineering
  • Nebraska Space Grant Consortium
  • University of Nebraska–Lincoln
  • Virginia Tech

Tags

Readers

  • Electrical Engineering
  • Geochemistry
  • Nanoscale Plasmonic Nanotechnology

Technology Areas

  • AI & ML
  • Autonomy
  • Microelectronics