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arXiv · 1712.03741

A review about w{\"u}stite Fe 1-z O, pseudo-phases and defect clustering

Jean-Raymond Gavarri·Claude Carel
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Abstract

Thermodynamic properties and structural aspects of the non-stoichiometric w\"ustite Fe 1-z O, and its modifications-the so-called pseudo-phases-as functions of composition z and equilibrium temperature are reviewed from 1960 to present (159 references). The focus is first put on the complexity of the equilibrium phase diagram. The first order transition W $\rightleftharpoons$ W' is specified on the boundary iron/ w\"ustite close to 1185 K. Transitions correlated to the modifications Wi at T(W) > 1185 K and W'j at 1185K < T(W') < T(W) (i and j =1,2,3) are reexamined. Structural determinations based on point defects and their clustering are recalled. A series of equilibria are developed, trying to justify the stabilization of the pseudo-phases, which can be interpreted in terms of transformation of defect clusters, or their mode of distribution (percolation, superstructure) including changes in electronic charge carriers.

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Jean-Raymond Gavarri, Claude Carel. 2017-12-11. A review about w{\"u}stite Fe 1-z O, pseudo-phases and defect clustering. https://arxiv.org/abs/1712.03741

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