**1. Introduction**

Progress in increasing competitiveness, i.e. the application of operational and more cost-effective control of corrosion properties, requires new approaches to the study of austenitic steels. In general, these steels are studied in terms of the atomiccrystalline state of austenite, as the main component of their structural state, namely, the parameters of the crystal lattice, grain size, the presence of packaging defects and dislocations, and so on. However, a comprehensive assessment of properties for one parameter is complicated, and in some cases impossible.

Since the bulk of these steels is paramagnetic austenite, and with a certain chemical composition or hardening, its amount can reach 100%, it is proposed to study these steels from the standpoint of the atomic-magnetic state. That is, to consider austenite primarily as a paramagnetic, which is characterized by a peculiar electronic structure, for which the supersensitive parameter is the specific

paramagnetic susceptibility χ<sup>0</sup> (the total magnetic moment per unit mass of austenite at a single value of the magnetic field). In this case, the parameter χ<sup>0</sup> is an integral characteristic of the formed austenite due to various factors (chemical composition, smelting conditions, deformation, heat treatment, etc.). It should be noted that most studies are devoted to the study of the magnetic susceptibility of χ steel (not χ<sup>0</sup> austenite), which may contain both austenite and α-phase: δ-ferrite, α0 -martensite of deformation (after cold compressive plastic deformation).

There is almost no information about the relationship between the magnetic state of austenite and corrosion properties. Thus, the assumption of predicting the corrosion properties of austenitic steels by the structural-magnetic state (parameter χ0) of austenite, which does not contain or contains a very low amount of α-phase (δ-ferrite, α0 -martensite), requires theoretical, experimental and practical confirmation.

Establishing a correlation between the atomic and magnetic state of austenite and corrosion is of theoretical and practical importance. Some of the information related to this problem is debaTable and insufficiently researched.

It is known from scientific sources that the low content (�0.005 … 0.5%) of the α-phase can dramatically affect the corrosion properties, which necessitates the introduction of supersensitive methods for its determination. The question of the influence of individual phases, which are simultaneously present in the austenitic matrix, remains unresolved.

The corrosion properties of chromium-nickel steels are affected by the casting temperature, chemical composition, carbides, heat treatment, deformation, harmful impurities, etc. No single physical parameter has been identified that would simultaneously and unambiguously take into account the influence of these factors on the properties of these steels. Therefore, for this purpose, a sensitive parameter is proposed—the specific paramagnetic susceptibility of χ<sup>0</sup> austenite.

Therefore, when determining the performance of austenitic steel products, along with the study of the crystal structure, it is advisable to study the relationship between the atomic and magnetic state of austenite with the corrosion properties.
