TU Darmstadt / ULB / TUbiblio

Atomistic Simulation of Grain Boundary Effects in a high Entrophy Alloy

Utt, Daniel Thomas (2017):
Atomistic Simulation of Grain Boundary Effects in a high Entrophy Alloy.
Darmstadt, TU Darmstadt, [Master Thesis]

Abstract

The following master thesis deals with atomistic simulations of grain boundaries (GBs)in a CuNiCoFe HEA, focusing on Cu segregation and mechanical properties under tensile load. The alloy will be described by an embedded-atom method (EAM) poten-tial; Monte Carlo (MC) molecular statics (MS), and molecular dynamics (MD) methods will used.

First we will investigate the mechanical and thermodynamic features described by the interatomic potential. We will compare characteristic values like lattice constants, elastic constants, and stacking fault energies to literature references and investigate the enthalpy of mixing for the different binary subsystems. The influence of the configurational entropy onto the phase stability of the HEA will be studied under the assumption of ideal Cu demixing.

The thermodynamics of Cu segregation will be studied on a Σ = 11(332) bicrystal. The mechanical properties of this bicrystal will be studied under tensile loading. The yield strength of a Cu, Ni, a perfectly random HEA, and a chemically equilibrated HEA sample will be compared. Cu, Ni, random CuNiCoFe, and a chemically equilibrated HEA nano crystal will be subjected to tensile straining. Their yield strength and grain growth tendencies will be investigated.

Item Type: Master Thesis
Erschienen: 2017
Creators: Utt, Daniel Thomas
Title: Atomistic Simulation of Grain Boundary Effects in a high Entrophy Alloy
Language: English
Abstract:

The following master thesis deals with atomistic simulations of grain boundaries (GBs)in a CuNiCoFe HEA, focusing on Cu segregation and mechanical properties under tensile load. The alloy will be described by an embedded-atom method (EAM) poten-tial; Monte Carlo (MC) molecular statics (MS), and molecular dynamics (MD) methods will used.

First we will investigate the mechanical and thermodynamic features described by the interatomic potential. We will compare characteristic values like lattice constants, elastic constants, and stacking fault energies to literature references and investigate the enthalpy of mixing for the different binary subsystems. The influence of the configurational entropy onto the phase stability of the HEA will be studied under the assumption of ideal Cu demixing.

The thermodynamics of Cu segregation will be studied on a Σ = 11(332) bicrystal. The mechanical properties of this bicrystal will be studied under tensile loading. The yield strength of a Cu, Ni, a perfectly random HEA, and a chemically equilibrated HEA sample will be compared. Cu, Ni, random CuNiCoFe, and a chemically equilibrated HEA nano crystal will be subjected to tensile straining. Their yield strength and grain growth tendencies will be investigated.

Place of Publication: Darmstadt
Divisions: 11 Department of Materials and Earth Sciences > Material Science > Materials Modelling
11 Department of Materials and Earth Sciences > Material Science
11 Department of Materials and Earth Sciences
Date Deposited: 03 Nov 2017 12:29
Referees: Albe, Prof. Dr. Karsten and Durst, Prof. Dr. Karsten
Export:
Suche nach Titel in: TUfind oder in Google

Optionen (nur für Redakteure)

View Item View Item