Influence of the heat treatment on the crystallization mechanisms of Al85Y5Ni8Co2 metallic glass

Real time synchrotron studies on amorphous Al85Ce5Ni8Co2 and Al85Y5Ni8Co2 alloys

“…However, some peaks remain un-indexed indicating an unknown phase. This microstructure is in agreement with our XRD studies [25] and the work of Bassim et al [26]. As the temperature approaches to the Al melting point, the Al-peaks become less intense (614 • C) and finally disappear (760 • C).…”

“…The first crystalline phase appears at 381 • C, which can be identified as ␣-Al. This is in agreement with the literature on Al-TM-RE and Al-Ni-Y-TM alloys [10,11,13,14,25], the primary crystallization of ␣-Al takes place during the first crystallization stage. The Al crystallites are homogeneously dispersed in the residual amorphous matrix.…”

Deformation induced primary crystallization in a thermally non-primary crystallizing amorphous Al85Ce8Ni5Co2 alloy

“…The advantages of nanoscale microstructures for the mechanical properties of partially crystallized amorphous alloys [4,5] draw attention to the significance of new methods for the control of nanocrystal synthesis. In most cases, during the annealing of glassy Al-rich amorphous precursors containing rare earth and transition metal additions, primary crystallization of a-Al takes place [6][7][8]. High densities of Al-nanocrystals with an average size of 8-10 nm were observed in the Al 90 Fe 5 Gd 5 , Al 88 Y 7 Fe 5 , Al 92 Sm 8 and Al 90 Ce 6 Ni 4 alloys [9][10][11].…”

“…In most cases, during the annealing of glassy Al-rich amorphous precursors containing rare earth and transition metal additions, primary crystallization of a-Al takes place [6][7][8]. High densities of Al-nanocrystals with an average size of 8-10 nm were observed in the Al 90 Fe 5 Gd 5 , Al 88 Y 7 Fe 5 , Al 92 Sm 8 and Al 90 Ce 6 Ni 4 alloys [9][10][11]. Generally, the crystallization sequence in these Al-rich systems strongly depends on the concentration of the alloying constituents, e.g., single primary a-Al precipitation in Al-Ce-Ni alloys is not observed above 4-6 at.% of Ce [11,12].…”

Severe plastic deformation induced nanocrystallization of melt-spun Al85Y8Ni5Co2 amorphous alloy

“…Annealing this alloy leads to the formation of primary fcc-Al nanocrystals with an average diameter of 5-15 nm [7,8] ing ultra high nucleation frequency and sluggish grain growth [9]. Al-based amorphous nanocomposites produced by isothermal annealing of amorphous precursors can drastically improve their mechanical properties [10].…”