Structure and embrittlement of metallic glasses

Structural characterisation of Al–Ni powders produced by gas atomisation

“…It should be noticed that the cooling rate in the gas atomisation process is of the same order of magnitude as the one achieved when producing metallic glasses by the melt-spinning technique. In the case of melt spun ribbons, the heat treatment of the melt before quench has been found to have a large impact on the structure on the atomic level but also on the microstructure of the solidification product as well as on the vitrifiability of the alloy [25][26][27][28]. Accordingly, it may be anticipated that this is also the case for a gas-atomised droplet and that the phase content of a solidified droplet will significantly depend on the production parameters, i.e.…”

Physical properties of the liquid Pd–18at.% Si alloy

“…This state is either inherited from the heterogeneous initial crystalline ingot or it develops after that the components are mixed at a temperature slightly above liquidus. The existence of a microheterogeneous state effects the microstructure of the solidified material and it furthermore influences the microstructure of amorphous ribbons obtained by rapid solidification (melt-spinning) [2][3][4][5]. The existence of the microheterogeneous state manifests itself in measurements of different physical properties as anomalous temperature variations during heating-cooling cycles in a temperature region above the liquidus.…”

Isothermal annealing induced embrittlement of Zr41.25Ti13.75Ni10Cu12.5Be22.5 bulk metallic glass

“…One is that high temperature isothermal annealing leads to precipitation of nano-scale crystallines and then strengthens the annealed alloys [15][16][17]. The other believes that the annealing process reduces flow agents such as free volumes and makes the plastic deformation more difficult and thus embrittlement induced [18][19][20]. Since there are such controversies, it is meaningful to clarify the influence of isothermal annealing done at some special temperatures on the mechanical behavior of a Zr-Ti-Ni-Cu-Be bulk metallic glass and to give reliable explanations based on the analysis of structural change during annealing treatment.…”