FERRITE SINTERED MAGNET

• Main Authors: MURAKAWA KIDO, ISHIKURA TOMOKAZU, IKEDA MAKI, MORITA HIROYUKI, MUROYA SHOGO
• Format: Patent
• Language: English; Japanese
• Published: 01.04.2021
• Subjects: ARTIFICIAL STONE; BASIC ELECTRIC ELEMENTS; CEMENTS; CERAMICS; CHEMISTRY; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDINGMATERIALS; CONCRETE; ELECTRICITY; INDUCTANCES; LIME, MAGNESIA; MAGNETS; METALLURGY; REFRACTORIES; SELECTION OF MATERIALS FOR THEIR MAGNETIC PROPERTIES; SLAG; TRANSFORMERS; TREATMENT OF NATURAL STONE

To provide a ferrite sintered magnet which is small in the dependence on a preliminary baking temperature, and which allows a superior magnetic property to be achieved with stability.SOLUTION: A ferrite sintered magnet according to the present invention comprises ferrite particles having a hexagonal structure. The ferrite sintered magnet contains metal elements at the atomic ratios as represented by the formula (1) below. Ca1-w-xRwSrxFezCom (1). In the formula (1), R's are at least one element selected from a group consisting of a rare earth element and Bi, and include at least La. In the formula (1), w, x, z and m satisfy requirements of the following expressions (2) to (5): 0.360≤w≤0.420 (2); 0.110≤x≤0.173 (3); 8.51≤z≤9.71 (4); and 0.208≤m≤0.269 (5). The ferrite sintered magnet is 45% or less in the fluctuation coefficient of diameters of crystal grains in a cross section in parallel with a c-axis.SELECTED DRAWING: Figure 1 【課題】仮焼温度への依存が少なく、優れた磁気特性を安定して得ることが可能なフェライト焼結磁石を提供することを目的とする。【解決手段】本発明は、六方晶構造を有するフェライト粒子を含むフェライト焼結磁石であって、フェライト焼結磁石は金属元素を下記式（１）で表される原子比で含む。式（１）中、Ｒは希土類元素及びＢｉからなる群より選ばれる少なくとも１種の元素であってＬａを少なくとも含む。式（１）中、ｗ、ｘ、ｚ及びｍは、下記式（２）〜（５）を満たす。上記フェライト焼結磁石はさらにｃ軸に平行な断面における結晶粒子の径の変動係数が４５％以下である。Ｃａ１−ｗ−ｘＲｗＳｒｘＦｅｚＣｏｍ・・・（１）０．３６０≦ｗ≦０．４２０・・・（２）０．１１０≦ｘ≦０．１７３・・・（３）８．５１≦ｚ≦９．７１・・・（４）０．２０８≦ｍ≦０．２６９・・・（５）【選択図】図１