The influence of processes that occur upon large degrees of drawing deformation on magnetic and mechanical properties of patented steels with 0.24 and 0.7% C is studied. Correlational relationships between magnetic and mechanical characteristics are established. The magnitude of magnetic characteristics is shown to allow evaluation of strength and plastic properties, as well as of the extent of damage to wires being deformed. INTRODUCTIONStructural transformations, which occur in steel under plastic deformation by drawing to large degrees of total reduction, are accompanied by considerable change in the most important physical and mechanical properties of the steel. For example, patented cold-drawn wire with a structure of fine-lamellar pearlite is a material that possesses the highest values of processing strength to be achieved (~5000-5200 MPa) [1].The level of strength to be achieved in a patented wire by drawing is determined to a large degree by its ultimate plasticity. In the course of plastic deformation of patented wire, complex physical processes take place in both ferrite and cementite components of pearlite. There are papers that report the formation of the cellular substructure [2][3][4][5][6][7][8][9][10][11][12][13] in ferrite plates; changes in the chemical composition of cementite upon deformation [14][15][16][17][18][19][20][21][22] and, consequently, in its physical-mechanical properties; the formation of metastable ferric carbide with a higher carbon content [15,16,23,24]; and a partial dissociation of cementite at large deformations. All these processes differently affect the ability of a patented wire to be deformed and lose plasticity, i.e., the phenomenon of "overhardening."Although a large number of studies are devoted to the investigation of both the structure of fine-lamellar pearlite with various degrees of dispersion and the changes in such a structure during deformation [4-6, 11-13, 17, 25-46], the physical nature of processes that take place upon deformation and annealing of a finelamellar ferrite-carbide mixture in patented steel remains somewhat unclear. In particular, this confusion concerns large degrees of deformation when the plasticity of a cold-worked wire decreases. The mechanism of cementite decomposition, the location of free carbon, and the effect of these processes on the plasticity are also unclear. Therefore, the study of changes in physical-mechanical properties of a patented wire at large degrees of drawing deformation is of considerable interest.We are not aware of any studies that report results on investigation of changes in the complex of magnetic properties of patented steels subjected to high extents of drawing (>95%). Thus, when studying the magnetic properties of patented wire after drawing, we pursued two goals. The first is to analyze the regularities of changes in magnetic properties of specimens at large deformations, which would give additional information on the evolution of the structural state of the material. The second is to compare changes in magne...

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The mechanical, magnetic, and thermal properties of water-quenched (from 1150 ° C) alloys, such as ç 36 ä 10 í 3, ç 36 ä 10 ï5í 2, and ç 36 ä 5 í 2, which were strengthened by aging (at 650 ° C) and high-temperature deformation (1100-800 ° C) followed by aging, are studied. The decomposition of a supersaturated solid solution in the Invar alloys under study was shown to increase the strength properties and coercive force but to decrease the plasticity and saturation magnetization. In this case, the aging ambiguously affects thermal expansion coefficient α of the different alloys; the temperature range of invariance decreases. The plastic deformation of Invars was found to increase the ultimate strength, yield strength, and coercive force. The additional aging of deformed materials increases the strength and decreases the plastic properties; among the magnetic parameters, the saturation magnetization exhibits the most adequate correlation with the mechanical properties. The thermal properties (the α coefficient and invariance range) resulting from the complex heat treatment differ slightly from those resulting from the single aging.