Influence of atomic size mismatch on binary alloy phase diagrams

Author(s):  
M. Fèvre ◽  
C. Varvenne ◽  
A. Finel ◽  
Y. Le Bouar
2006 ◽  
Vol 510-511 ◽  
pp. 290-293 ◽  
Author(s):  
Pyuck Pa Choi ◽  
Ji Soon Kim ◽  
O.T.H. Nguyen ◽  
Dae Hwan Kwon ◽  
Young Soon Kwon

Al-La-Ni-Fe alloys of three different compositions (Al82La10Ni4Fe4, Al85La9Ni3Fe3 and Al88La6Ni3Fe3) were prepared high-energy milling in a planetary ball-mill (AGO-2). Complete amorphization was observed for the Al82La10Ni4Fe4 alloy after milling for 350 h at a rotational speed of 300 rpm. In contrast, the Al85La9Ni3Fe3 and Al88La6Ni3Fe3 powders contained the FCC Al phase even for prolonged milling. The amorphization tendency was found to increase in the order of Al88La6Ni3Fe3 < Al85La9Ni3Fe3 < Al82La10Ni4Fe4, which may well be ascribed to the increasing atomic size mismatch of the constituent elements on La addition. DSC analyses of amorphous samples revealed two-stage crystallization processes for all three alloys, however, with strong variations in the thermal stability upon compositional changes. As observed by SEM, amorphous powders consisted of particles with nearly spherical shape and diameters ranging from 5 to 20 µm.


1998 ◽  
Vol 58 (5) ◽  
pp. 518-524 ◽  
Author(s):  
A Benyoussef ◽  
D Dohmi ◽  
A Elkenz

MRS Bulletin ◽  
2007 ◽  
Vol 32 (8) ◽  
pp. 620-623 ◽  
Author(s):  
R. Busch ◽  
J. Schroers ◽  
W. H. Wang

AbstractBulk metallic glasses (BMGs) are multicomponent alloys with typically three to five components with large atomic size mismatch and a composition close to a deep eutectic. Packing in BMG liquids is very dense, with a low content of free volume resulting in viscosities that are several orders of magnitude higher than in pure metal melts. The dense packing accomplished by structural and chemical atomic ordering also brings the BMG-forming liquid energetically and entropically closer to its corresponding crystalline state. These factors lead to slow crystallization kinetics and consequentially to high glass-forming ability. This article highlights the thermodynamic and kinetic properties of BMGs and their contributions to extraordinarily high glass-forming ability. Some possible links with mechanical properties are also suggested.


Sign in / Sign up

Export Citation Format

Share Document