Project Details
Projekt
Polymer bonded textured composites with single crystalline NiMn-based MSM particles for magnetic-field controlled dampers and actuators
Applicant
Professor Dr. Oliver Gutfleisch
Subject Area
Materials Science
Term
from 2006 to 2014
Project identifier
Deutsche Forschungsgemeinschaft (DFG) - Project number 28238542
Magnetic shape memory (MSM) alloys are a new class of magnetically driven active materials that show large strains of up to 10% in single-crystal Ni2MnGa of 7M modulated martensitic structure. The magnetic field induced movement of twin boundaries can be exploited for actuators, sensors and, as it is an energy dissipating process, also for vibration damping devices. However, single-crystals of Ni2MnGa are difficult to prepare and cannot easily support significant tensile stresses as they are inherently very brittle. One solution is the use of aligned MSM particles suspended in a stiffness-matched polymer matrix. In this project, MSM particles will be produced from melt-extracted Ni2MnGa fibres. This, in the field, unique method simplifies the preparation of single-crystal martensitic particles by an appropriate heat treatment. Composites will then be produced by embedding the particles in a polymer matrix. Materials processing, characterisation and modelling will be used to optimise magnetic and magnetoplastic properties, which depend on particle alignment, size and shape of the particles as well as packing density but also on thermal and mechanical properties of the polymer. One further advantage of the here to be developed composites could be that the typical threshold behaviour of single-crystal Ni2MnGa could be moderated by tailoring their magnetic, thermal and magneto-mechanical properties.
DFG Programme
Priority Programmes
