An investigation of ferromagnetic phases in manganese rich alloys

The investigation of ferromagnetic phases in the manganese indium, manganese antimony carbon and the manganese magnesium alloy systems was conducted mainly by means of x-ray diffraction methods and where ever permissible by metal1ographic examination. The manganese indium and the manganese antimony carbon alloys were prepared in the vacuum melting furnace in an argon atmosphere, while the manganese magnesium alloys were prepared by sinter-compact techniques. Heat treatments were carried out in tube furnaces in an argon atmosphere. Ferromagnetic phases were not found in either the manganese indium or the manganese magnesium systems. The presence of the compound Mn₃In in the manganese indium system was established. The compound has a gamma brass structure with a lattice parameter a₀ = 9.413 A°. In the manganese magnesium system only solid solutions of manganese and magnesium were found to exist. The manganese solid solution was not magnetic suggesting that the addition of magnesium atoms did not give the degree of separation of manganese atoms for favourable ferromagnetic conditions. It was concluded also that the manganese atoms in the compound Mn₃In were not sufficiently separated for favourable ferromagnetic conditions. The ferromagnetic phase found in the manganese antimony carbon alloys was attributed to the compound Mn₂Sb. This suggested that elements in Group Vb which are strongly electronegative to manganese and form stable binary compounds, do not tend to form ternary compounds containing carbon.Applied Science, Faculty ofMaterials Engineering, Department ofGraduat