Metallic Glasses, Quasicrystals and their Nanocomposites
Synthesis and Characterization of Metallic Glasses, Quasicrystalline-Glass Composites in some Zr/Cu-Based Alloys
- Editore:
LAP Lambert Academic Publishing
- EAN:
9783659620881
- ISBN:
3659620882
- Pagine:
- 164
- Formato:
- Paperback
- Lingua:
- Tedesco
Descrizione Metallic Glasses, Quasicrystals and their Nanocomposites
The endeavours made in this book are intended to study the effect of material tailoring on the crystallization behaviour, glass forming ability and structure/microstructure of Zr/Cu-based metallic glasses and nanoquasicrystal-glass composites. The substitution of Ga on Al site in Zr-Al-Cu-Ni alloy affects the nucleation and growth characteristics of quasicrystals and consequently changes the morphology of nanoquasicrystals. A new metallic glass composition; Zr-Ga-Cu-Ni with glass transition temperature (Tg); 614 K has been observed. The addition of Ti destabilizes the glassy phase in (Zr-Al-Cu-Ni)Ti alloys. Formation of single quasicrystalline phase by annealing the glass has been found for the alloys. The size of quasicrystal grain decreases with increase of Ti. Rapidly solidified ribbons of Cu-Ga-Mg-Ti and Cu-Al-Mg-Ti alloys show the formation of ¿-brass type phase, which is an approximant of quasicrystals. The Cu-Ga-Mg-Ti alloy display ordered ¿-brass structure, whereas Cu-Al-Mg-Ti leads to the formation of amorphous and nanocrystalline disordered bcc ¿-brass phase. Electron diffraction patterns have been found to show a close structural similarity with the icosahedral phase.
