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arXiv · 2111.04346

Thermogravimetric study of the non-stoichiometric w\"ustite FeOx. Pseudo phases w i and w' i . New T-P-X equilibrium phase diagram

Pierre Vallet·Claude Carel
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Abstract

A statistical numerical analysis of thermogravimetric measurements (temperature, mass variation, oxygen pressure) leads to a new equilibrium phase diagram T-P-X of the iron monoxide or w\"ustite FeOx. Three varieties or pseudo phases W1, W2, W3 are revealed above 911 {\textdegree}C, three others W'1, W'2, W'3 below. This diagram displays their subfields, and shows 25 invariant points between stable phases and 8 possible invariant points between metastable phases. A thermodynamic approach is pointed out, which makes possible to characterize the point defects and their clusters as components of the crystal lattice.

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Pierre Vallet, Claude Carel. 2021-11-08. Thermogravimetric study of the non-stoichiometric w\"ustite FeOx. Pseudo phases w i and w' i . New T-P-X equilibrium phase diagram. https://arxiv.org/abs/2111.04346

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