Parametric Study of Amorphous High-Entropy Alloys formation from two New Perspectives: Atomic Radius Modification and Crystalline Structure of Alloying Elements

Abstract

Chemical and topological parameters have been widely used for predicting the phase selection in high-entropy alloys (HEAs). Nevertheless, previous studies could be faulted due to the small number of available data points, the negligence of kinetic effects, and the insensitivity to small compositional changes. Here in this work, 92 TiZrHfM, TiZrHfMM, TiZrHfMMM (M = Fe, Cr, V, Nb, Al, Ag, Cu, Ni) HEAs were prepared by melt spinning, to build a reliable and sufficiently large material database to inspect the robustness of previously established parameters. Modification of atomic radii by considering the change of local electronic environment in alloys, was critically found out to be superior in distinguishing the formation of amorphous and crystalline alloys, when compared to using atomic radii of pure elements in topological parameters. Moreover, crystal structures of alloying element were found to play an important role in the amorphous phase formation, which was then attributed to how alloying hexagonal-close-packed elements and face-centered-cubic or body-centered-cubic elements can affect the mixing enthalpy. Findings from this work not only provide parametric studies for HEAs with new and important perspectives, but also reveal possibly a hidden connection among some important concepts in various fields.

Solution-Processable 2D Polymer/Graphene Oxide Heterostructure for Intrinsic Low-Current Memory Device

“…According to this mechanism, we can analyze the role of 2D CMP for achieving a low-power consumption operation device. Due to their intrinsic microporous structure, some metal atoms diffuse into the CMP and form finer conductive filaments during metal deposition, , resulting in a low resistance state in the CMP-only diode (Figure c). Meanwhile, the inserted CMP layer weakens the internal electric field, and the weakened electric field could decelerate the migration of oxygen ions, accompanying with a lower reduction of p-rGO layer in our bilayer device compared to that in a p-rGO-only device, which leads to the low program current for low power (Figure c,d).…”

Lattice distortion-induced sluggish phase transition in CoCrFeNixAl1-x (x = 0.5, 0.75) high-entropy alloys at high pressures

“…However, no prominent electronic change of Co, Cr, Fe, Ni, and Al has been observed in this pressure range. Recently, 4f electrons in addition to the s and d electrons, have also counted as valence electrons [27]. Thus, the VEC values of the hcp HEAs GdTbDyTmLu, HoDyYGdTb, and YGdTbDyLu are 13, 9.8, and 10.6 respectively, being much higher than the value of 3 reported previously [3,28].…”

Design of coherent wideband radiation process in a Nd3+-doped high entropy glass system

“…A high-entropy system’s design strategy is to randomly distribute multiple nearly equal components in the crystal lattice, resulting in a significant increase in the configuration entropy of the system, even greater than the melting entropy of the system itself 27 . Under such circumstances, the proportions of each atom in the composite system are similar, and they all tend to be evenly distributed in space, forming a single-phase system 28 . The corresponding unit cell can easily form a simple stacked body-centered cubic (bcc) unit cell when the atom size differs.…”