Alloy design strategies for sustained ductility in Mg-based amorphous alloys – Tackling structural relaxation

The aim of this research is to clarify a quantitative evaluation in the structural relaxation processes focusing on the activation energy in Cu based amorphous alloys. The activation energy for structural relaxation process in a metal type amorphous CuHfTi ternary alloys, with cross sections of typically 0.03 mm x 2.0 mm, prepared by chill-block melt spinning has been investigated by Differential Scanning Calorimetry (DSC) with a cyclically heating technique. Activation energies for structural relaxation with a spatial quantity in amorphous materials have been discussed by use of a relaxed ratio function that depends on annealing temperature and time. In the present work, the distributions for the Activation Energy Spectrum (AES) were observed almost 152 kJmol-1 (1.58 eV). Another result has been also established that the “reversible” AES model energy distribution though the cyclically structure relaxation occurs even in amorphous Cu60Hf20Ti20 alloy.

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Alloy design strategies to increase strength and its trade-offs together

Progress in Materials Science ◽

10.1016/j.pmatsci.2020.100720 ◽

2020 ◽

pp. 100720 ◽

Cited By ~ 2

Author(s):

Seung Zeon Han ◽

Eun-Ae Choi ◽

Sung Hwan Lim ◽

Sangshik Kim ◽

Jehyun Lee

Keyword(s):

Alloy Design ◽

Design Strategies ◽

Trade Offs

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Kinetics of Reversible Structural Relaxation in Amorphous Alloys

High Temperature Materials and Processes ◽

10.1515/htmp.1999.18.1-2.1 ◽

1999 ◽

Vol 18 (1-2) ◽

pp. 1-8 ◽

Cited By ~ 3

Author(s):

Osami Haruyama,

Keyword(s):

Structural Relaxation ◽

Amorphous Alloys ◽

Kinetics Of

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Structural Relaxation of Open Volume in Hyper-Eutectic Zr-Cu-Al Bulk Amorphous Alloys Measured by Positron Annihilation

Defect and Diffusion Forum ◽

10.4028/www.scientific.net/ddf.373.130 ◽

2017 ◽

Vol 373 ◽

pp. 130-133

Author(s):

Taishi Ishiyama ◽

Kazukui Kobayashi ◽

Yoshihiko Yokoyama ◽

Toyohiko J. Konno ◽

Akihiro Iwase ◽

...

Keyword(s):

Positron Annihilation ◽

Structural Relaxation ◽

Amorphous Alloys ◽

Density Measurement ◽

High Strength ◽

Eutectic Alloys ◽

Ordered Structure ◽

Compositional Dependence ◽

Scanning Calorimetry ◽

Bulk Amorphous Alloys

The Zr-Cu-Al bulk amorphous (BA) alloys, which have no long-range ordered structure, possess various properties such as high strength and toughness with compositional dependence. In the present study, in order to estimate the natures of local structure change and relaxation behavior of hyper-eutectic BA alloys during annealing, positron annihilation measurements and density measurement have been performed for hyper-eutectic Zr-Cu-Al BA alloys with annealing. The enthalpy relaxation and structural relaxation was also measured by differential scanning calorimetry (DSC) measurement. These results show that the relaxation process of free volume containing in hyper-eutectic BA alloys is different from that in hypo-eutectic alloys.

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