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Matrix controlled structural phase transformations in embedded metallic nanoparticles

delete2022-05-01
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PRE
AI
C
Cain J. Hung
S
Sanjeev K. Nayak
L
Lucas R. Parent
R
Rainer J. Hebert
S
S. P. Alpay *
DOI:10.1016/j.scriptamat.2022.114632delete
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Abstract

Abstract

En 中文
Non-equilibrium synthesis and post-processing methods may result in unique and unexpected microstructures. In arc-melted and subsequently laser-glazed Al-0.5 at% Co alloys, we show via high-resolution transmission electron microscopy lattice-imaging that cobalt forms coherent face-centered cubic nanoprecipitates. Using first principles methods and a common-neighbor analysis, we explain the reasons for this and then expand the model by introducing nanoprecipitates of 4th-row transition metals into aluminum and titanium supercells. Our results indicate that the lattice strain and the physio-chemical interactions across the matrix-particle interface play significant roles in the crystal structure of the precipitate. Our computations make surprising predictions; for example, a hexagonal close packed copper can be stabilized in a titanium matrix and cubic zinc can be formed in an aluminum matrix. Extrapolating from these findings, we hypothesize that new allotropic forms of transition metals can be accessed through non-equilibrium processing and careful design of lattice strains.
Keywords:
Aluminum alloys
Density functional theory (DFT)
Nanoparticles
Phase transformations
Alloy design
Nanoprecipitates

Journal

Scripta Materialia cover
Scripta Materialia
IF:
5.6
Papers:
1.6W
Citations:
5.1W

Organization

U
University of Connecticut
Scholars:
2.4W
Papers: 2.2W
Citations: 2.5W