Smart Materials and Devices
Smart materials are characterized by their multifunctional properties, in particular, sensing and actuation functions. Important examples are shape memory alloys,(SMAs), piezoelectrics, as well as multiferroic materials. These materials show large abrupt changes of their physical properties near phase transformations. Therefore, they are predestined for applications on the micro- and nano-meter scale.
Shape memory alloys can be reversibly deformed by strain values exceeding 10% and still recover their original shape by heating (thermal shape memory effect) or by applying a magnetic field (magnetic shape memory effect). These properties are used for the development of novel smart actuators and multifunctional devices
- Multiphysics simulation of smart devices
- Multifunctional devices: Microgripper, Microvalves, Microscanner, Micropositioning, Microdamping
Smart materials are useful to convert waste heat or vibrational energy in electricity (energy harvesting). Another important topic is solid-state cooling. Shape memory alloys show very large changes of latent heat in the order of 20 J/g that are exploited for cooling and heat pumping applications.
Nanotechnologies are used to develop mechanically active nanostructures showing sensing and actuation functions. Novel in-situ measurement methods are being developed to characterize their physical properties in order to understand scaling and size effects.
Awarded for the Development an Realisation of an Ultra-compact Photodetector: Prof. C Koos, Prof. M. Kohl and Physicist S. Mühlbrandt (from left to right, Photo: T. Niedermüller, GSS).