PHASE EQUILIBRIA IN COPPER-RICH Cu-Mn-Sn ALLOYS.

The work presents the results of investigation of Cu-Mn-Sn phase diagrams in the Cu-rich concentration region (up to 30 mass. %) by differential thermal and metallographic analysis, with scanning electron microscopy and microhardness measurements. The analyses established beta , gamma , delta , epsilon , and theta phases which are at equilibrium with the Cu-based solid solution in the 700-350 degree C range. Within the concentration range studied, differential thermal analysis established the peritectic (L plus alpha reversible reaction beta ) type, three monovariant equilibria eutectoid type, and three nonvariant equilibria eutectoid type structures.