Typically, metallic melts crystallize when cooled from above their melting temperature. Some combinations of metals, however, exhibit a low desire and ability to crystallize, hence they don’t crystallize but freeze into a glass during solidification. Among these amorphous metals are bulk metallic glasses (BMGs), which exhibit a particular ease of glass formation even at cooling rates of 100 K/s or below. This allows for the first time to study the entire supercooled melt and crystallization processes within. The absence of dislocation and slip-planes in the amorphous structure of BMGs results in very high strength and elasticity, often times exceeding those in currently used structural materials. In our department we are interested in understanding these properties and utilizing this understanding for the development of new improved BMGs applying combinatorial approaches.
Another even more unusual feature of BMGs is their unique softening behavior; they soften from a high strength metal to a soft plastic when approaching their glass transition temperature. We utilize his highly non-linear softening to develop processing methods, which are inspired by the processing of thermo plastics. These include novel nanofabrication methods, 3D net-shaping of miniature parts, and macroscopic forming methods which allows to fabricate geometries that were previously unachievable with any metal processing method.
The combination of BMG properties and processability suggest to replace conventional metals, as well as plastics, in application, where high performance and precise fabrication are required.
Faculty involved with research:
– ME & MSE
– ME & MSE