Lattice-fringe imaging of precipitation-hardened cobalt rare-earth magnets

Abstract

The different microphases of high coercivity (Co, Fe, Cu, Zr)_7.5Sm permanent magnets have been studied and characterized by means of high-resolution electron microscopy. From lattice-fringe images of the cellular microstructure the misfit of the crystal lattice parameter between the coherent cell boundary phase and the cell interior phase is determined. It is shown that the platelet phase within the cell interiors consists of a hexagonal Co¹⁷Sm₂ layer.