Formation of phases with α-Mn and β-Mn structures in iron-based alloys

It is shown by X-ray diffraction, optical microscopy and DTA that in Fe-M-C alloys (M = Cr, Mo, W) the phases with α- and β-Mn type structures (the χ- and π-phases) can form under conditions of both equilibrium crystallization (the χ-phase) and nonequilibrium crystallization (the χ- and π-phases). For the π-phase to form it is necessary that the carbon content of the alloy fall in a particular range and that the melt be cooled at a high rate