Thermoplastic Forming of Bulk Metallic Glasses

Metallic glasses display interesting mechanical properties including high mechanical resistance and large capacity to store elastic energy. Since metallic glasses can now be produced in bulk conditions, they can be used for structural applications. In this new context, thermoforming of metallic glasses can be a particularly well adapted technique for production of small size components with good surface finish. As for other glasses, metallic glasses can be preferentially thermoformed in their supercooled liquid region. However, since metallic glasses are still emerging materials, the mechanisms of high temperature deformation remain not completely understood and intensive work is currently carried out to identify the elementary mechanisms of deformation. Moreover, since thermoforming is performed in the supercooled liquid region, the thermal stability of the glass to be formed is a key point for the success of the thermoforming process. Finally, it is also shown that thermoforming conditions can be used to produce multi materials associating metallic glasses and conventional metallic alloys.