New process to make huge spinel ferrite single crystals

A new method for preparing manganese-zinc ferrite single crystals is described. Huge ingots 90mm in diameter and 8OOmm long are grown using a combination of Bridgeman and zone leveling techniqes. The crystals are homogeneous throughout their length, except for bottom and top sections (≃ 50mm each). Crystals grown by the ordinary Bridgeman technique are inhomogeneous and consequently have a much larger variability in magnetic properties.