An alloy selection and processing framework for nanocrystalline materials

Nanocrystalline materials have a unique set of properties due to their nanometer-scale grain size. To harness these properties, grain growth in these materials needs to be suppressed, particularly in order to process bulk nanocrystalline components and to use them reliably. Alloying the material with the right elements has the potential to produce remarkably stable nanocrystalline states, particularly if the nanocrystalline state is thermodynamically stable against grain growth. This thesis builds upon previous models for selecting alloy combinations that lead to thermodynamic stability against grain growth, by developing frameworks that extend to negative enthalpy of mixing systems and ordered grain boundary complexions. These models are used to develop a generalized stability criterion based on bulk thermodynamic parameters, which can be used to select alloy systems that are formally stable against grain growth. A robust statistical mechanics framework is developed for reliable thermodynamic observations using Monte Carlo simulations to produce free energy diagrams and phase diagrams for stable nanocrystalline alloys.

Department dc:contributor.department

Massachusetts Institute of Technology. Department of Materials Science and Engineering

Grantor dc:publisher

Massachusetts Institute of Technology

Year dc:date.issued

2018

Author dc:creator

• Kalidindi, Arvind R.(Arvind Rama)

Advisor dc:contributor.advisor

• Christopher A. Schuh.

• Materials Science and Engineering.

Statement dc:rights

• MIT theses are protected by copyright. They may be viewed, downloaded, or printed from this source but further reproduction or distribution in any format is prohibited without written permission.

Licence dc:rights.uri

• http://dspace.mit.edu/handle/1721.1/7582

Language dc:language.iso

eng

Handle dc:identifier.uri

http://hdl.handle.net/1721.1/120208

OAI identifier oai:identifier

oai:dspace.mit.edu:1721.1/120208