Giving materials new functionalities? We are finding ways to do that in various projects in the field of »Programmable Materials«. What we find is that not only the basic material itself is changed, but also its internal structures.
New manufacturing methods make it possible to specifically produce structures in the micrometer range. These methods include for example, additive processes like 3D-printing. An engineer uses these methods not only to design the outer shape, but also to target the internal microstructures to give certain properties to a component. In cooperation with other Fraunhofer Institutes, we go one step further and define multiple states for such microstructures and apply external stimuli to switch between them.
Programmable Mechanics and a Tool Kit Full of Structural Possibilities
At Fraunhofer Cluster of Excellence »Programmable Materials«, we develop mathematical procedures for optimizing structures and provide support to engineers in designing production processes and choosing the appropriate microstructures. Working with the Fraunhofer Institute for Mechanics of Materials IWM, we develop the microstructures for 3D-printing, which can change the internal stiffness or the surface shape as desired when subjected to external mechanical stress. Specifically, we have achieved extraordinary mechanical effects that do not exist in the naturally occurring material.
For example, the so-called pentamode mechanical meta-materials are solid structures that behave like liquids. These materials consist of three-dimensional arrays of cubic cells. Each cell exhibits a non-linear mechanical behavior and multiple stable states. Such cells are developed, printed, and tested at Fraunhofer IWM.