Unique breakthrough in bulk metallic glass manufacturing

All initial studies on the sample conducted at Mid Sweden University (including the resilience and microscopy examination) support the claims that this first sample has indeed an amorphous structure, i.e. a structure that differs from a regular crystalline structure. Further thorough studies are under way and the results will be soon reported in a scientific publication.

This shiny tile attached to the solid stainless plate is unique in few aspects. Firstly, metallic glasses (also amorphous metals, BMG or glassy alloys) on their own have unique properties. They are extremely strong (2-15 times than crystalline counterparts), extremely elastic (golf clubs with a face made of BMG) and are often non-corrosive. Amorphous metals have also shown promising resistance against metal fatigue.

ARCAM, electron beam melting (EBM®), a member of the wide family of additive manufacturing technologies, makes it possible to manufacture components of extremely complex shapes within a single process.

"In many cases, additive manufacturing is both faster and less expensive than other, more mature manufacturing methods. In some cases it can yield components that are simply not possible to manufacture using other technologies. And the tile is made of the modern, iron-based BMG, which is relatively inexpensive, lighter than common steel and does not contain environmentally hazardous rare earth metals," says Mikael Bäckström.

Worldwide research of BMGs is driven by the promises of their unique properties. Many application areas, from engineering to biomedical implant manufacturing, can potentially be revolutionized by using advantages of BMGs.

Until now, the manufacturing of even small BMG components has been quite complex and very expensive. Making large BMG components using traditional manufacturing methods, like melt spinning, casting, powder metallurgy or thermoplastic forming, is not possible.

"In all cases when hot bulk components cool down slowly, the atoms have enough time to re-arrange into a regular crystalline structure. Only processes with an extremely quick cooling period, when the atoms "freeze" from the disordered liquid state very quickly, result in BMG formations. This is why until now, we have only been able to manufacture small or rather thin BMG components," says Mikael Bäckström.

The success of the present research makes a new opening promising to revolutionize the manufacturing of the products and components made from such unique materials as BMG. Preliminary results have already shown that the weight of commercial products can be reduced by 90 % if the technology is exploited. Application areas in need of strong non-corrosive elastic materials are likely to be the main winners of applying the BMGs.

The originator of the worldwide patent for beam based additive manufacturing of amorphous metals is owned by the Swedish company Exmet AB. This ensures the commercial success for the verified technology and future licensees.