Atomistic Kinetic Monte Carlo Simulations of the Quenching of a Binary

Alloy

Tim Drews, Dan Finkenstadt, Xuemin GuUniversity of Illinois at Urbana-Champaign

Atomic Scale SimulationsPreliminary Report

10/18/00

Introduction

• The prediction of the microstructural properties of alloys is of interest because the microstructure strongly influences the bulk properties of the alloy

• Purpose: To study the thermodynamic properties of quenching a binary alloy system

• Perform kinetic Monte Carlo simulations in the Canonical ensemble (e.g. constant NVT)

• The parameters that we are interested in studying are the pair correlation function, the dynamic structure factor, the final structure of the alloy after quenching, and the phase diagram

Kinetic Monte Carlo Method

Move Do Nothing

Nearest Neighbor Sites

0 1

0 1

1 2 3 4 5 6 7 8

kT

Eexp

actXV

XV

2,1i

ixxi

iyi

actXV )nun(

2

1E

0.4

Jump Frequency and Potential Function

Methodology

• How do we know if our model is working?• Comparison to results from Athenes, et al. for the Fe-Al system

• Where will we get data from to parameterize the model?• System 1: Fe-Al system• System 2: Ni-Al system

• What parameter space do we want to probe with the model?

• Simulations with several pairs of concentrations and temperatures to construct a phase diagram