TY - THES

T1 - The effects of grain size on the elastic response of FeCrMnNiCo high entropy alloy

T2 - a molecular dynamics study

AU - Zetterberg, Keegan

N1 - no embargo

PY - 2023

Y1 - 2023

N2 - In this work, molecular dynamics was used to investigate the effect of grain size and temperature on the elastic constants and hardness of CoCrFeMnNi high entropy alloy through atomistic simulations. Grain sizes of up to 4 nm to 20 nm were simulated, across a temperature range of 100 to 1000 Kelvin.The systems were equilibrated using a conjugate gradient style minimization followed by an NpT ensemble. Elastic constants were calculated using the deformation method, and for polycrystalline systems, averaged using Hill’s averaging method. When available, the results proved to be well in agreement with experiment and other atomistic simulations. The elastic constants were found to increase with grain size on this scale.In addition to the elastic response, the plastic response was quantified by calculating the hardness through nanoindentation. The grain size effects on flow stress were examined, and this work shows an inverse Hall-Petch relationship for the Cantor alloy.

AB - In this work, molecular dynamics was used to investigate the effect of grain size and temperature on the elastic constants and hardness of CoCrFeMnNi high entropy alloy through atomistic simulations. Grain sizes of up to 4 nm to 20 nm were simulated, across a temperature range of 100 to 1000 Kelvin.The systems were equilibrated using a conjugate gradient style minimization followed by an NpT ensemble. Elastic constants were calculated using the deformation method, and for polycrystalline systems, averaged using Hill’s averaging method. When available, the results proved to be well in agreement with experiment and other atomistic simulations. The elastic constants were found to increase with grain size on this scale.In addition to the elastic response, the plastic response was quantified by calculating the hardness through nanoindentation. The grain size effects on flow stress were examined, and this work shows an inverse Hall-Petch relationship for the Cantor alloy.

KW - Hochentropie-Legierung

KW - CoCrFeMnNi

KW - Cantor-Legierung

KW - Molekulardynamik-Simulationen

KW - Nanoindentation

KW - Linearer WAK

KW - Elastische Konstanten

KW - Polykristalline Systeme

KW - Korngrößeneffekte

KW - Paarweises Potenzial

KW - Äquilibrierung

KW - Elastische Module

KW - Umgekehrte Hall-Petch-Beziehung

KW - Streckspannung

KW - Härte

KW - Hall-Petch-Beziehung

KW - Nanoskalige Materialien

KW - Mechanische Eigenschaften

KW - Atomistische Simulationen

KW - LAMMPS

KW - Temperaturabhängigkeit

KW - High Entropy Alloy

KW - CoCrFeMnNi

KW - Cantor Alloy

KW - Molecular Dynamics Simulations

KW - Nanoindentation

KW - Linear CTE

KW - Elastic Constants

KW - Polycrystalline Systems

KW - Grain Size Effects

KW - Pairwise Potential

KW - Equilibration

KW - Elastic Moduli

KW - Inverse Hall-Petch Relationship

KW - Yield Stress

KW - Hardness

KW - Hall-Petch Relationship

KW - Nanoscale Materials

KW - Mechanical Properties

KW - Atomistic Simulations

KW - LAMMPS

KW - Temperature Dependence

U2 - 10.34901/mul.pub.2023.202

DO - 10.34901/mul.pub.2023.202

M3 - Master's Thesis

ER -