Coherency and Surface Stress Effects on Phase Stability of Isolated Nanoparticles

Abstract:

The coherent phase equilibria of binary nanoparticles, in which three phases can be formed, were examined by accounting for the particle size effect engendered by the surface stress. Considering the system geometry exhibiting radial symmetry, coherent phase diagrams could be constructed for different particle sizes. The phase diagrams exhibited several characteristics of phase equilibria unique to coherent systems. It was found that a positive surface stress results in a radial compressive stress in the particle that is inversely proportional to the particle radius, thereby increasingly stabilizing the phase having a lower molar volume as the particle size decreases.

• Periodical: Solid State Phenomena (Volumes 121-123)
• Pages: 979-982
• DOI: https://doi.org/10.4028/www.scientific.net/SSP.121-123.979
• Online since: March 2007
• Authors: Joo Youl Huh, Heon Lee, William C. Johnson
• Keywords: Coherent Phase Diagram, Misfit Strain, Nanoparticle, Phase Stability, Surface Stress

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