A method and device for reversibly attaching a phase changing metal to an object
Sensors, Devices and Components
We offer a new technology to transfer small and fragile objects using switchable adhesive properties of the liquid and the solid phase of a metal. Using a metal with a low melting temperature the phase transformation can be easily manipulated without applying much energy. Gallium (Ga) and Ga-containing alloys are good candidates for this purpose as their melting temperatures ranges from 30°C to 50°C and therefore only a slow temperature increase is required for the phase transformation. Using an elastomer and dipping this elastomer into the liquid metal phase the metal droplet will wet the elastomer surface and attach to it. Then, this stamp with a liquid metal droplet can be brought in contact with an object of interest. By lowering the temperature, the metal droplet will change its phase from liquid into solid. This phase transformation leads to the strong attachment between the object and the elastomer. This state features a strong adhesion and can be used to transfer the object. For detachment it is sufficient to slightly increase the temperature above the melting temperature of the metal (Fig. 1).
Our results (Fig. 2) show that after detachment the metal droplet remains on the elastomer without leaving any rests or contaminations on the object and can be simply reused.
- Enabling to transfer sensitive and fragile objects
- Enhanced controllability and functionality
- Applicable to wet and rough surfaces
- Repeatedly reusable metal droplet
- Applicable in transfer printing, robotics, electronic packaging, and biomedicine
Ye, Z., Lum, G. Z., Song, S., Rich, S. and Sitti, M. (2016), "Phase Change of Gallium Enables Highly Reversible and Switchable Adhesion", Adv. Mater. doi:10.1002/adma.201505754
EP patent application filed in February 2016.
- Ref.-No.: 0104-5132-BC (663.6 KiB)
Dr. Bernd Ctortecka, M. Phil.
Phone: +49 89 / 29 09 19-20