| 摘要 |
PURPOSE:In a Bridgman process, to obtain the titled single crystal at a low cost, having uniformity in one or more component compositions, by subjecting several kinds of different ferrite raw materials having a composition for compensating a composition segregation to successive band dissolution. CONSTITUTION:For example, in preparing a single crystal of Mn-Zn ferrite by Bridgman process, a raw material having a given composition comprising Fe2O3, MnO and ZnO is put in a crucible, and it is melted completely in a furnace. This crucible is taken out of the furnace, another ferrite raw material having a composition capable of compensating a composition segregation is put on the raw material previously melted, the crucible is returned to the furnace again and the rametrial is melted. When the raw material fed later is melted well with the raw material fed first at the contact part, whole the crucible is moved in the direction of the upper part of the furnace, and all the raw materials are solidified. The crucible is then lowered gradually, and melted from the tip part, so that it is made into a single crystal. |
