POWDER MAGNETIC CORE, INDUCTOR, AND METHOD FOR MANUFACTURING POWDER MAGNETIC CORE

• Main Authors: SHIMA HIROSHI, URATA KENRI, KOBAYASHI KENICHIRO, YAMAKI MAKOTO, MIKOSHIBA SHUN, ONISHI NAOTO
• Format: Patent
• Language: English; Japanese
• Published: 22.03.2024
• Subjects: BASIC ELECTRIC ELEMENTS; ELECTRICITY; INDUCTANCES; MAGNETS; SELECTION OF MATERIALS FOR THEIR MAGNETIC PROPERTIES; TRANSFORMERS

To provide a powder magnetic core which realizes downsizing and a low loss in a high frequency region at the same time.SOLUTION: A powder magnetic core according to an embodiment of the present disclosure is a powder magnetic core with magnetic powders attached to the core by a binder layer. The powder magnetic core includes magnetic powders in the concentration of at least 88 volume%. A cross-sectional picture of the powder magnetic core is taken by a scan-type electron microscope. The region where the taken area of the cross-sectional picture is at least 10000 μm2 is divided by the unit region of a 0.5 μm×0.5 μm square. A unit region of the divided unit regions in which the cross-sectional area of a binder is at least 50% of the unit region is extracted as a specific unit region. When the number of the extracted specific unit regions to the number of the whole unit regions is the area ratio of the binder, the area ratio of the binder is in the range of 0.2% to 3.0%, both inclusive.SELECTED DRAWING: Figure 1 【課題】小型化を実現しつつ、高周波領域において低損失を実現可能な圧粉磁心を提供すること。【解決手段】本開示の一態様にかかる圧粉磁心は、磁性粉末がバインダ層を介して結着された圧粉磁心である。圧粉磁心は８８体積％以上の磁性粉末を含有しており、圧粉磁心の断面写真を走査型電子顕微鏡を用いて撮影し、断面写真の撮影面積が１００００μｍ２以上の領域を０．５μｍ×０．５μｍの正方形を単位領域とする領域で分割し、分割された単位領域のうちバインダの断面積が５０％以上を占める単位領域を特定単位領域として抽出し、前記単位領域全体の数に対する前記抽出された特定単位領域の数の割合をバインダが占める面積比とした場合、バインダが占める面積比が０．２％以上３．０％以下である。【選択図】図１