This paper presents an analysis of the Fe—Ni phase diagrams published over the last 50 years. It is shown that the differences in the low-temperature part of the phase diagram and in the explanation of the nature of invar alloys are due to the lack of clear experimental evidence for the absence or occurrence of a superstructure with less than 50% Ni content. The experimental results obtained in this work favor a certain particular phase diagram yet unpublished in the reference literature and suggest the possible nature of invar effect. The phase diagram analysis and the assumption on the nature of the invar effects are based on results obtained by structural methods.

Keywords: text Fe!-!Ni<$> diagram, invar effect, microdomains, discontinuous coagulation, discontinuous decomposition, reverse α → γ transformation PACS: 61.50.ks, 61.66.Dk, 64.70.K− (all) DOI: 10.3367/UFNe.2018.02.038298 URL: https://ufn.ru/en/articles/2018/10/e/ 000454141800005 2-s2.0-85059188627 2018PhyU...61.1000Z Citation: Zemtsova N D "Some discussion topics on the representation of the equilibrium Fe—Ni phase diagram and on the nature of the invar effect" Phys. Usp. 61 1000–1015 (2018) BibTexBibNote ® (generic)BibNote ® (RIS)MedlineRefWorks Received: 4th, July 2017, accepted: 14th, February 2018 Оригинал: Земцова Н Д «К дискуссии по вопросам представления равновесной фазовой диаграммы Fe—Ni и природы инварного эффекта» УФН 188 1103–1118 (2018); DOI: 10.3367/UFNr.2018.02.038298