Novel meta-phase arising from large atomic size mismatch

Matter ◽  
2022 ◽  
Author(s):  
Kunpeng Zhao ◽  
Chenxi Zhu ◽  
Wujie Qiu ◽  
Shiqi Yang ◽  
Hong Su ◽  
...  
Keyword(s):  
Size Mismatch ◽  
Atomic Size

Al-La-Ni-Fe Amorphous Alloys and Amorphous-Crystalline Composites Produced by Mechanical Alloying

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
Keyword(s):  
Spherical Shape ◽  
High Energy ◽  
Size Mismatch ◽  
Atomic Size ◽  
Stage Crystallization ◽  
Dsc Analyses ◽  
Amorphous Powders ◽  
Compositional Changes ◽  
La Addition ◽  
Constituent Elements

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.

Thermodynamics and Kinetics of Bulk Metallic Glass

MRS Bulletin ◽  
2007 ◽  
Vol 32 (8) ◽  
pp. 620-623 ◽  
Author(s):  
R. Busch ◽  
J. Schroers ◽  
W. H. Wang
Keyword(s):  
Metallic Glasses ◽  
Pure Metal ◽  
Glass Forming Ability ◽  
Kinetic Properties ◽  
Size Mismatch ◽  
Atomic Size ◽  
Glass Forming ◽  
Thermodynamics And Kinetics ◽  
Metal Melts ◽  
Kinetics Of

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.

scholarly journals Microstructure and Hardness of Scandium Trialuminide with Ternary Rare-Earth Additions

2007 ◽  
Vol 539-543 ◽  
pp. 1565-1570 ◽  
Author(s):  
Yoshihisa Harada ◽  
David C. Dunand
Keyword(s):  
Solid Solution ◽  
Rare Earth ◽  
Lattice Parameter ◽  
Second Phase ◽  
Micro Hardness ◽  
Size Mismatch ◽  
Atomic Size ◽  
Rare Earth Additions ◽  
Re Elements ◽  
Vickers Micro Hardness

The microstructure of ternary Al3(Sc1-yREy) intermetallic compounds (where RE is one of the rare-earth elements La, Ce, Nd, Sm, Eu, Yb or Lu), was investigated as a function of RE concentration for 0<y≤0.75. Alloys with La, Ce, Nd, Sm or Eu additions consist of a L12 phase containing a dendritic second phase with D019 (La, Ce, Nd, Sm) or C11b (Eu) structure. Alloys with Yb or Lu additions show a single L12 phase. The RE solubility limits at 1373 K in the L12-Al3(Sc1-yREy) phase are very low for La, Nd, Ce and Eu (0.08-0.41 at.% or y=0.0032-0.0164), low for Sm (3.22 at.% or y=0.1288) and complete for Yb and Lu. The lattice parameter of the L12 solid-solution increases linearly with RE concentration and the magnitude of this effect is correlated with the atomic size mismatch between Sc and the RE elements. The Vickers micro-hardness of the L12 solid-solution increases linearly with increasing RE concentration.

scholarly journals Atomic size mismatch strain induced surface reconstructions

2008 ◽  
Vol 92 (6) ◽  
pp. 062104 ◽  
Author(s):  
Jessica E. Bickel ◽  
Normand A. Modine ◽  
Anton Van der Ven ◽  
Joanna Mirecki Millunchick
Keyword(s):  
Size Mismatch ◽  
Atomic Size ◽  
Mismatch Strain ◽  
Surface Reconstructions

scholarly journals Understanding solute effect on grain boundary strength based on atomic size and electronic interaction

2020 ◽  
Vol 10 (1) ◽  
Author(s):  
Zhifeng Huang ◽  
Ping Wang ◽  
Fei Chen ◽  
Qiang Shen ◽  
Lianmeng Zhang
Keyword(s):  
Grain Boundary ◽  
Interfacial Strength ◽  
Atomic Radius ◽  
Electronic Interaction ◽  
Size Mismatch ◽  
Atomic Size ◽  
Electronic Interactions ◽  
Strength Based ◽  
Grain Boundary Embrittlement ◽  
Boundary Strength

Abstract Solute segregating to grain boundary can stabilize the microstructure of nanocrystalline materials, but a lot of solutes also cause embrittlement effect on interfacial strength. Therefore, uncovering the solute effect on grain boundary strength is very important for nanocrystalline alloys design. In this work, we have systematically studied the effects of various solutes on the strength of a Σ5 (310) grain boundary in Cu by first-principle calculations. The solute effects are closely related to the atomic radius of solutes and electronic interactions between solutes and Cu. The solute with a larger atomic radius is easier to segregate the grain boundary but causes more significant grain boundary embrittlement. The weak electronic interactions between the s- and p-block solutes and Cu play a very limited role in enhancing grain boundary strength. While the strong d-states electronic interactions between transition metallic solutes and Cu can counteract embrittlement caused by size mismatch and significantly improve the grain boundary strength. This work deepens our understanding of solute effects on grain boundary strength based on atomic size and electronic interactions.

Pt 2AuCuNiSn, a High Entropy Alloy with a Large Atomic Size Mismatch

2019 ◽  
Author(s):  
Bjoern Winkler ◽  
Erick A. Juarez-Arellano ◽  
Wolfgang Morgenroth ◽  
Andrei Barkov ◽  
Ann-Christin Dippel ◽  
...  
Keyword(s):  
High Entropy Alloy ◽  
Size Mismatch ◽  
Atomic Size ◽  
High Entropy

scholarly journals Concentration Fluctuations in Liquid Alloys of Alkali Metals from Semiempirical Theories of Mixtures

1985 ◽  
Vol 40 (4) ◽  
pp. 425-429
Author(s):  
L. J. Gallego ◽  
J. A. Alonso ◽  
J. A. Somoza
Keyword(s):  
Alkali Metals ◽  
Concentration Fluctuations ◽  
Size Difference ◽  
Liquid Alloys ◽  
Size Mismatch ◽  
Atomic Size ◽  
Binary Liquid

The semiempirical theories of mixtures developed by van Laar, Margules, Scatchard-Hamer, Wilson and Renon and Prausnitz are used to study the concentration fluctuations of binary liquid alloys formed among the alkali metals. Examination of the fitting capabilities of these theories leads to the conclusion that those of van Laar, Scatchard-Hamer and Renon and Prausnitz are appropriate both when the atomic sizes of the component metals are similar and when there is considerable atomic size mismatch. The Margules and Wilson theories, on the contrary, appear to be restricted only to cases in which the size difference between the two types of atoms is small.

Misfit Stresses Caused by Atomic Size Mismatch: The Origin of Doping-Induced Destabilization of Dicalcium Silicate

2016 ◽  
Vol 16 (6) ◽  
pp. 3124-3132 ◽  
Author(s):  
Peng Guo ◽  
Bu Wang ◽  
Mathieu Bauchy ◽  
Gaurav Sant
Keyword(s):  
Dicalcium Silicate ◽  
Size Mismatch ◽  
Atomic Size

scholarly journals Experimental and theoretical evidence of charge transfer in multi-component alloys – how chemical interactions reduce atomic size mismatch

2021 ◽  
Author(s):  
Luis Casillas Trujillo ◽  
Barbara Osinger ◽  
Rebecka Lindblad ◽  
Dennis Karlsson ◽  
Alexei I Abrikosov ◽  
...  
Keyword(s):  
Thin Films ◽  
Density Functional Theory ◽  
Charge Transfer ◽  
Photoelectron Spectroscopy ◽  
Density Functional ◽  
Functional Theory ◽  
Size Mismatch ◽  
Atomic Size ◽  
X Ray ◽  
Theoretical Evidence

Ab-initio simulations of a multi-component alloy using density functional theory (DFT) were combined with experiments on thin films of the same material using X-ray photoelectron spectroscopy (XPS) to study the...

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