Autori: Axinte Eugen & Marius Chirileanu

Editorial: dr.Kurshid Zaman, Bentham Science Publishers, Recent Patents in Materials Science , vol.5,nr.3 , p.10, 2012.

Rezumat:

Metallic Glasses (MGs) , called also bulk metallic glasses (BMGs) ( or glassy metals , amorphous metals , liquid metals) are considered to be the materials of the future. Bulk metallic glasses, formed at very low critical cooling rates, are different from traditional amorphous alloys (which are usually formed at high cooling rates) in order to avoid the crystallization . The most important feature of BMGs that distinguish them from ordinary amorphous materials is the glass transition that transforms super cooled liquids into a glassy state when cooled from high to low temperature Some scientists frantically investigated the mechanisms of BMG formation, dynamics of metallic glass formation, the atomic structure, the micromechanisms of mechanical properties, etc. They also explore the atomic-scale mechanisms of BMG formation and to search for new bulk glassy alloys and composites with improved glass-forming ability. Other scientists are oriented rather to BMGs fabrication and industrialization. Professor Wei Zhu Wang, leader of KX4 Key Laboratory of Extreme Conditions from Institute of Physics (IOP), Chinese Academy of Sciences (CAS) , Beijing, declared that „currently there are more than 30 groups work on the science, preparation and applications of the BMGs” One of the most active groups in China , KX4 (group of Amorphous Materials and Physics in the IOP-CAS) have developed a series of rare earth based RE-BMGs with functional physical properties, and also focuses on the some fundamental issues in this field. In US there are some important groups that successfully activate in BMGs domain . The US groups (the team from Schroerslab-Yale leaded by dr. Jan Schroers and the group from Caltech leaded by professor Marios Demetriou ) are more focused on BMGs practical aspects (production ,industrialization, biomedical materials , aerospace materials) . Unfortunately, the environmental capabilities of bulk metallic glasses (BMGs) are not sufficient elucidated by scientists. However , in this article , some environmental aspects of BMGs using and industrialization are investigated : the biocompatibility of most BMGs , the obtaining of valuable BMGs from wastes , using of BMGs in green energy applications ( solar cells, hydrogen production), the using of BMGs in catalyst systems and the possibilities for using metallic glasses in systems for retention and purification of dangerous polutants.

Cuvinte cheie: new alloys , metallic glasses, glass forming ability , atomic structure, processing; environmental , biomedical, defense, aerospace, green energy

URL: http://www.benthamscience.com/mats/