Effect of magnetic transition on the character of martensitic transformations in Fe-Mn-based alloys

• Belous I.A.

  Candidate of Physical and Mathematical Sciences Associate Professor, Chair of Information Technology and System
  Vladivostok State University of Economics and Service
  Vladivostok. Russia

• Lecturer, Academic College
  Vladivostok State University of Economics and Service
  Vladivostok. Russia

In this paper generalizes the results of studies of Fe-Mn alloys doped with C, Si, Co, Cr, Ni. The profile of the lines (111) γ-phase, (101) ε-phase and (100) α-phase for determining the phase composition were recorded on the diagram tape at a velocity of 1/4 deg/min; the error was 3%. To determine the parameters of the crystal lattice, the interference lines were recorded at a velocity of 1/8 deg/min, the calculation was carried out along the lines (222)α1 for austenite and (100)α1, (002)α1, (101)α1 for the ε-phase. Electronscroscopic studies were performed on the microscope MES-100 at accelerating voltage of 75 kV. Deformation of samples at high temperatures was carried out at the IMASH-5S-65 plant, or, using special devices for stretching at elevated and low temperatures, at the universal breaking machine “Amesler”. To determine the impact conditions for obtaining a ε-phase on the phase composition in the process of deformation of samples of size 6х6х12 mm; x-ray diffraction studies of the phase composition depending on the temperature of deformation was carried out five times for the explosive samples with pre-printed flats.

Installed: the influence of the conditions of the emergence of the ε-phase (above or below TN) may occur due to the structural distribution of the hexagonal phase, because the band ε-phase formed from paramagnetic austenite tend to have a preferential orientation in one system; increased susceptibility to the formation of α-martensite after annealing and the simultaneous increase in the number of layers with the FCC lattice in ε-phase during plastic deformation make it possible to implement the assumption of ε→γ→α scheme. It is shown that magnetic state of austenite has an influence on the completeness and properties of the formed hexagonal phase; the tendency vysokorazvityh alloys to the formation of α-martensite depends on the magnetic state of austenite, magnetic restructuring in the ε-phase has no effect on the amount of generated in the process of plastic deformation of α-martensite.

Keywords: Fe-Mn alloys, alloying alloys, austenite, magnetic alteration.