Al-based Metallic-Glass Alloys - Practical Electron Microscopy and Database - - An Online Book - |
||||||||
Microanalysis | EM Book https://www.globalsino.com/EM/ | ||||||||
================================================================================= | ||||||||
Figure 3053a shows the critical cooling rate (Rc) and critical casting thickness (dc) for formation of various metallic glass alloys from melts as a function of reduced glass transition temperature (Trg).
Figure 3053a. Critical cooling rate and critical casting thickness for formation of various metallic glass alloys from melts as a function of reduced glass transition temperature. The Al-based metallic-glass alloys are in green. Figure 3053b shows the microstructure of an Al87Ni7Cu3Ce3 amorphous alloy. In the HAADF-STEM (Z-contrast) image, some brightest spots in white circles represent heavy Ce atoms or its small clusters (Z=58), while some darkest areas in red circles represent fcc-Al (Z=13) nanostructures in the amorphous matrix. However, the HRTEM image does not present clearly the structures of fcc-Al nanocrystals.
Figure 3053b. (a) HAADF-STEM image and (b) HRTEM image of an Al87Ni7Cu3Ce3 amorphous alloy. Adapted from [1]
[1] Eiji Abe, Atomic-Scale Characterization of Nanostructured Metallic Materials by HAADF/Z-contrast STEM, Materials Transactions, 44(10), 2035-2041, (2003).
|
||||||||
================================================================================= | ||||||||
|
||||||||