Composite Magnetic Body for High-Frequency Impedance

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

Conventional metal magnetic bodies have poor frequency characteristics of impedance, making them unsuitable for high-frequency electronic components, despite having better DC bias characteristics compared to ferrites.

Innovation Solution

A composite magnetic body comprising soft magnetic metal particles and non-magnetic ceramic particles with a smaller particle size, specifically a silicate compound, is used to improve both DC bias and frequency impedance characteristics, preventing interfacial reaction phases and optimizing the amount and circularity of ceramic particles to enhance performance.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If the amount of non-magnetic ceramic particles is increased, then frequency characteristic of impedance is improved, but formability deteriorates

Engineering Contradiction:

Improvefrequency characteristic of impedanceVSAvoidformability

Core Design Contradiction:

ReliabilityVSEase of manufacture

Solution Approach 1:

The patent optimizes the amount of non-magnetic ceramic particles to a specific range (0.6-90 parts by weight per 100 parts of soft magnetic metal particles) to balance frequency impedance performance and formability. This parameter optimization ensures that sufficient ceramic particles are present to improve frequency characteristic while maintaining enough metal particles to ensure proper formability and structural integrity.

Inventive Principle:

Principle #35Parameter changes

2Manufacturing precision

If non-magnetic ceramic particles with high circularity are used, then manufacturing precision is improved, but DC bias characteristic and frequency characteristic deteriorate

Engineering Contradiction:

Improvecircularity of particlesVSAvoidDC bias characteristic and frequency characteristic

Core Design Contradiction:

Manufacturing precisionVSReliability

Solution Approach 1:

The patent specifies that non-magnetic ceramic particles should have a circularity of less than 0.98, deviating from the conventional preference for high circularity particles. This parameter change improves DC bias and frequency impedance characteristics, demonstrating that slightly lower circularity particles provide better performance despite marginally reduced manufacturing precision.

Inventive Principle:

Principle #35Parameter changes

Applied Scientific Principles

This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.

Function Achieved in This Case

The composite magnetic body achieves improved DC bias and frequency impedance characteristics, shifting the self-resonant frequency to higher values, making it suitable for high-frequency applications while maintaining formability and strength.

Implementation Method 1

soft magnetic metal particles

Methodology Applied

Scientific EffectMagnetic properties: Magnetism

Implementation Method 2

a frequency characteristic of impedance is improved. Here, 'a frequency characteristic of impedance is improved' means that a self-resonant frequency (SRF) of the composite magnetic body shifts to a higher frequency side

Methodology Applied

Scientific EffectImpedance characteristic: Electrical Resistance

Data Source

PatentUS11605483B2Composite magnetic body and electronic component

Publication Date: 2023.03.14 TDK CORP

AI summary

A composite magnetic body includes soft magnetic metal particles and non-magnetic ceramic particles each having a particle size (D50) smaller than that of the soft magnetic metal particles.