Yu. V. Subachev

The influence of an elastic uniaxial deformation of a medium-carbon steel on its magnetostriction in the longitudinal and transverse directions

In order to reveal the role of magnetostriction in the formation of a magnetic texture that appears in steels during their elastic deformation, the influence of stresses during uniaxial loading on the behavior of several magnetic characteristics of medium-carbon steel 45 was investigated. The magnetic parameters were measured under the conditions of a closed magnetic circuit with the application of attachable transducers along and across the direction of the applied load. The results of measurements of the hysteresis and magnetostriction properties of the investigated steel were compared. The magnetic parameters that monotonically change with an increase in the applied stresses were established.

The influence of a preliminary plastic deformation on the behavior of the magnetic characteristics of high-strength controllably rolled pipe steel under an elastic uniaxial tension (Compression)

The influence of a preliminary plastic deformation, which models the initial stressed–strained state (SSS) of an article, on the behavior of the magnetic characteristics of pipe steel of the X70 (K60) strength class under elastic tension and compression was investigated. The magnetic characteristics of specimens were measured both under the conditions of a closed magnetic circuit and using attachable transducers along and across the applied-load direction. The prehistory in the form of plastic deformation has an effect on the regularities in changes in the magnetic parameters of a material upon the next elastic deformation as a consequence of plastic-deformation-introduced residual stresses of different levels. This indicates the necessity to consider the initial SSS of a metal structure when developing magnetic methods for determining the parameters of their SSS during operation.

The effects of deformations by rolling and uniaxial tension on the structure and the magnetic and mechanical properties of armco iron, steel 12X18H10T, and a steel 12X18H10T-Armco Iron-Steel 12X18H10T composite material

The effects of elasto-plastic deformations by rolling and uniaxial tension on the structure and the magnetic and mechanical properties of Armco Iron, 12X18H10T steel, and a three-layer Steel 12X18H10T-Armco Iron-Steel 12X18H10T model composite material are investigated. The magnetic characteristics, which vary uniquely during elasto-plastic deformations, thus allowing their use as parameters for estimating mechanical properties and the degree of deformation by rolling and uniaxial tension in items made of these materials, are determined.

Effect of elastoplastic deformation on magnetic characteristics of a powder structural steel having different residual porosities

The effect of porosity on the evolution of magnetic characteristics of a powder structural steel during deformation up to failure is shown by an example of steel 50H2M. The selection of a magnetic field such that the coercive force in a minor magnetic hysteresis loop weakly depends on the porosity is shown to be possible. It is supposed that the applied stress at which the minimum coercive force of such a minor hysteresis is observed corresponds to internal stresses of the porous material.

The influence of elastic deformations on the hysteresis properties of a two-layer ferromagnet composed of components with magnetostrictions of opposite signs

The influence of an elastic deformation that is produced by an uniaxial extension (compression) on the behavior of several magnetic characteristics of Armco iron and nickel, whose magnetostrictions have opposite signs, and a two-layer material composed of them was studied. The magnetic characteristics were measured both under the conditions of a closed magnetic circuit and using attachable transducers along and across the direction of an applied load. The results are explained from the standpoint of the formation of magnetic anisotropy, which is induced by the action of normal stresses. The results of measurements of the hysteresis and magnetostriction properties of the investigated materials are compared. The magnetic parameters of the investigated materials that monotonically change with an increase in the applied stresses are determined.

Effect of heat treatment and elastoplastic deformation on magnetic properties of 50Ni2Mo powder steel

The paper studies the effect of heat treatment modes and uniaxial tension on the magnetic properties, internal stress and specific resistance of 50Ni2Mo powder steel. It is shown that when treated and mechanically loaded in the elastic range and weak magnetic fields, the steel reveals anomalous behavior of its magnetic characteristics such as coercive force, maximum permeability and residual induction. The observed anomalous behavior is analyzed in the framework of physical mesomechanics and is associated with porosity of the powder material. It is demonstrated that physical mesomechanics and magnetic measurements hold promise as an efficient tool of research in porous ferromagnetic materials in various effective external fields. The thus studied magnetic characteristics allow efficient control of heat treatment modes of 50Ni2Mo powder steel.

Effect of heat treatment on the magnetic behaviour of powder steel 50Ni2Mo under uni-axial tension:

In this study, investigation results on the effect of heat treatment conditions on the mechanical properties, internal stresses, magnetic characteristics, and electrical resistivity of powder steel 50Ni2Mo are presented. Coercive force and maximum magnetization are shown to be applicable as magnetic test parameters to reveal underheating for quenching. Heating for quenching above the critical point A c 3 up to 910°С has an insignificant effect on the mechanical characteristics of the steel tested. It has been demonstrated that the use of the coercive force measured on minor magnetic hysteresis loops is preferable when estimating the level of applied tensile stresses in heat-treated powder steel 50Ni2Mo.

Behavior of magnetic characteristics of structural powder ЖГр steels during rolling and subsequent tension

Results of investigations into the effect of tensile deformation on the magnetic characteristics of powder carbon steels preliminarily rolled to different degrees of plastic deformation are reported. The effect of plastic deformation on the strength characteristics of powder steels having different porosities and carbon contents is discussed. The possibility of estimating the mechanical properties of powder steels by magnetic methods is considered.

Structure and electromagnetic properties of ZhGr-type powder steel deformed by rolling with different porosity and temper

The results of studying the structure and electromagnetic properties of powder construction steels of the ZhGr type with different temper (0.03, 0.45, and 0.95 wt %) and porosity (8, 12, and 18%) after deformation by rolling to the degree of strain ɛ = 30% and a step of 0.5–6.0% are presented. The data of microstructure studies that indicate anisotropy of the structural elements in the direction of rolling are presented, and typical types of pores are identified and described. The porosity value of steels with any composition is halved when the strain is about 30%; here, the maximal magnetization monotonically increases because the volumetric portion of pores decreases.

The effect of sizes of particles of furnace charge on magnetic characteristics of a sintered iron powder

The results of studies of the effect of particle sizes of iron powder on magnetic and electric characteristics of iron sintered materials are discussed. The contributions from different stages of producing specimens to formation of pore sizes are considered, and the results of metallographic studies are discussed.