Publications by authors named "E M Bringa"

The magnetic properties of Ni nanoparticles (NPs) with diameter D are investigated using spin-lattice dynamics (SLD) simulations. Using exchange interactions fitted to ab-initio results we obtain a Curie temperature, , similar, but lower, than experiments. In order to reproduce quantitatively the bulk Curie temperature and the experimental results, the exchange energy has to be increased by 25% compared to the ab-initio value.

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We study the effects of the chemical short-range order (SRO) on the thermal conductivity of the refractory high-entropy alloy HfNbTaTiZr using atomistic simulation. Samples with different degrees of chemical SRO are prepared by a Monte Carlo scheme. With increasing SRO, a tendency of forming HfTi and TiZr clusters is found.

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Article Synopsis
  • The study investigates the plastic properties of a high-entropy alloy (HfNbTaTiZr) using simulated nanoindentation tests, comparing it to a standard Ta crystal.
  • Key findings reveal that the high-entropy alloys exhibit less dislocation relaxation and minimal dislocation emission compared to the Ta crystal, indicating unique dislocation behavior.
  • The presence of short-range order in the alloy increases its stiffness and hardness, leads to a larger plastic zone and higher dislocation density, and eliminates twinning plasticity, contrasting with the behavior of the elemental Ta under stress.
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Compression of a magnetic material leads to a change in its magnetic properties. We examine this effect using spin-lattice dynamics for the special case of bcc-Fe, using both single- and poly-crystalline Fe and a bicontinuous nanofoam structure. We find that during the elastic phase of compression, the magnetization increases due to a higher population of the nearest-neighbor shell of atoms and the resulting higher exchange interaction of neighboring spins.

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We investigate by molecular dynamics simulation the mechanical behavior of concentrated alloys under nanoindentation for the special example of single-phase fcc Fe[Formula: see text]Ni[Formula: see text] alloys. The indentation hardness is maximum for the equiatomic alloy, [Formula: see text]. This finding is in agreement with experimental results on the strength of these alloys under uniaxial strain.

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