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Thermal surface free energy and stress of iron.

ABSTRACT: Absolute values of surface energy and surface stress of solids are hardly accessible by experiment. Here, we investigate the temperature dependence of both parameters for the (001) and (110) surface facets of body-centered cubic Fe from first-principles modeling taking into account vibrational, electronic, and magnetic degrees of freedom. The monotonic decrease of the surface energies of both facets with increasing temperature is mostly due to lattice vibrations and magnetic disorder. The surface stresses exhibit nonmonotonic behaviors resulting in a strongly temperature dependent excess surface stress and surface stress anisotropy.

SUBMITTER: Schonecker S

PROVIDER: S-EPMC4594358 | biostudies-literature | 2015 Oct

REPOSITORIES: biostudies-literature

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Thermal surface free energy and stress of iron.

Schönecker Stephan S Li Xiaoqing X Johansson Börje B Kwon Se Kyun SK Vitos Levente L

Scientific reports 20151006

Absolute values of surface energy and surface stress of solids are hardly accessible by experiment. Here, we investigate the temperature dependence of both parameters for the (001) and (110) surface facets of body-centered cubic Fe from first-principles modeling taking into account vibrational, electronic, and magnetic degrees of freedom. The monotonic decrease of the surface energies of both facets with increasing temperature is mostly due to lattice vibrations and magnetic disorder. The surfac ...[more]

PMID: 26439916

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