Formation and properties of Au-based nanograined metallic glasses

Influence of grain size and composition, topology and excess free volume on the deformation behavior of Cu–Zr nanoglasses

“…Indirect experimental evidence for the existence of interfaces in NGs have been provided by Gleiter et al [2][3][4][5][6][7]. The recent work of Chen et al [8], supports Gleiter's results on the structural model of a NG. The microstructure of a metallic nanoglass consisting of glassy grains and glass-glass interfaces has been experimentally revealed by electron microscopy, small-angle X-ray scattering and positron annihilation spectroscopy [9], while molecular dynamics studies showed that glass-glass interfaces exhibit an excess free volume and a modified local order [10,11].…”

“…The influence of interfaces on the deformation behavior of nanoglasses has been shown both in computer simulation [11,13,14] and experiment [9,15], where also an enhanced plasticity under compression was observed indicating that not critical shear bands occur. Recent experiments on sputtered nanograined Au-based glasses also showed high hardness and a low elastic modulus as compared to their bulk counterparts [8].…”

The Way from Today's Materials to New Kinds of Amorphous Solids: Nano-glasses

“…If the Young's moduli of a Sc 75 Fe 25 nano-glasses (Chokshi et al, Franke et al -unpublished) and Au 52 Ag 5 Pd 2 Cu 23 Si 10 Al 6 nano-glasses (Chen et al 2011) are compared with the Young's moduli of the corresponding melt-quenched glassy ribbons, the moduli of the nano-glasses were found (in all cases studied so far) to be higher. As the atomic density in the nano-glass interfaces is reduced in comparison to the density of melt-quenched glasses with the same chemical composition (Fig.…”

“…5) has been applied so far to Aubased and a Ti-based metallic glasses (Chen et al 2011(Chen et al , 2013. The targets used were mixtures of the alloy elements in the form of powders with a particle size of about 100 o C. The background gas pressure was lower than 10 -4 Pa and the working pressure was 0.67 Pa.…”

“…(1) -should be catalyzed by a heterogeneous catalyst because the catalyst is reusable and the co-product of this oxidation process would be non-polluting hydrogen gas Chauhan et al 2009;Mitsudome et al 2009;Yang and Nieh 2007;Sond et al 2010). The Au 52 Ag 5 Pd 2 Cu 25 Si 10 Al 6 nano-glass (called Au-based NGMG in equation 1) was noted (Chen et al 2011) to exhibit a high catalytic activity.…”