Accession Number:

ADA551865

Title:

Applying Massively Parallel Kinetic Monte Carlo Methods to Simulate Grain Growth and Sintering in Powdered Metals

Descriptive Note:

Master's thesis

Corporate Author:

NAVAL POSTGRADUATE SCHOOL MONTEREY CA

Personal Author(s):

Report Date:

2011-09-01

Pagination or Media Count:

121.0

Abstract:

Kinetic Monte Carlo KMC simulation methods were utilized to study the grain growth and sintering of nanocrystalline metal compacts. Sintering is the process used to fabricate materials from powders by densifying the powder compact at elevated temperatures. Recently, experimental literature has demonstrated that nanoparticles 50 nm can be used to bond materials at dramatically lower temperatures and pressures while maintaining the mechanical properties of nanostructured materials. Despite these promising results, the grain growth and sintering mechanisms of nanostructures are not fully understood. Simulations performed using KMC algorithms can be used to model nanoparticle grain growth and sintering. Sandia National Laboratories new, massively-parallel, Stochastic Parallel Particle Kinetic Simulator SPPARKS code is capable of simulating large-scale problems of grain growth and sintering from the nanoscale to the microscale. This thesis focused on setting up SPPARKS on the Naval Postgraduate Schools high performance computing resources. The performance of SPPARKS was assessed for large-scale simulations of grain growth and sintering. Using SPPARKS, the ability to perform coupled grain growth and sintering was demonstrated while controlling variables such as temperature, porosity, and grain size. The results demonstrate the importance of the spatial distribution of porosity on the nanostructure evolution during grain growth and sintering.

Subject Categories:

  • Fabrication Metallurgy
  • Numerical Mathematics
  • Computer Programming and Software

Distribution Statement:

APPROVED FOR PUBLIC RELEASE