FeCoBSiPCu Alloy Powder for High Yield Magnetic Components

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing Fe-based amorphous alloy powders for electronic components like noise filters and choke coils face challenges in achieving high saturation magnetic flux density and low coercive force, while maintaining a large particle diameter, which is essential for improving yield and magnetic characteristics.

Innovation Solution

The development of FeCoBSiPCu alloy powder with a composition formula of Fe100-a-b-c-d-e-f Coa Bb Si c P d Cu e C f, where 3.5 ≤ a ≤ 4.5 at%, 6 ≤ b ≤ 15 at%, 2 ≤ c ≤ 11 at%, 3 ≤ d ≤ 5 at%, 0.5 ≤ e ≤ 1.1 at%, and 0 ≤ f ≤ 2 at%, primarily featuring an amorphous phase or a mixed amorphous and crystal phase structure, to enhance amorphous forming ability and magnetic properties.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Productivity

If the particle diameter of alloy powder is increased to improve yield, then productivity is improved, but saturation magnetic flux density decreases and coercive force increases

Engineering Contradiction:
ImproveyieldVSAvoidmagnetic characteristics
Core Design Contradiction:
ProductivityVSReliability

Solution Approach 1:

The invention changes the chemical composition parameters of the alloy by precisely controlling the content of Co (3.5-4.5 at%), B (6-15 at%), Si (2-11 at%), P (3-5 at%), Cu (0.5-1.1 at%), and C (0-2 at%). This parameter optimization enables the alloy to form an amorphous phase structure that maintains excellent magnetic characteristics (saturation magnetic flux density ≥1.6 T and coercive force ≤100 A/m) even when the particle diameter is large (90 μm or less), thus resolving the contradiction between yield improvement and magnetic property maintenance.

Inventive Principle:
Principle #35Parameter changes

2Ease of manufacture

If Fe content is reduced to improve amorphous forming ability, then ease of manufacture is improved, but saturation magnetic flux density decreases

Engineering Contradiction:
Improveamorphous forming abilityVSAvoidsaturation magnetic flux density
Core Design Contradiction:
Ease of manufactureVSReliability

Solution Approach 1:

The invention creates a composite alloy system FeCoBSiPCuC that combines multiple elements with complementary functions. Co and B serve as primary amorphous-forming elements, while Fe provides magnetic properties. The synergistic combination of these elements enables the alloy to achieve both high amorphous forming ability and high saturation magnetic flux density, resolving the contradiction between ease of manufacture and magnetic performance.

Inventive Principle:
Principle #40Composite materials

3Ease of manufacture

If Co content is increased to improve amorphous forming ability, then ease of manufacture is improved, but device complexity increases due to composition control

Engineering Contradiction:
Improveamorphous forming abilityVSAvoidcomposition control
Core Design Contradiction:
Ease of manufactureVSDevice complexity

Solution Approach 1:

The invention optimizes the Co content to a specific range (3.5-4.5 at%) that provides sufficient amorphous forming ability without excessive complexity. This precise parameter control, combined with coordinated adjustment of other elements (B: 6-15 at%, Si: 2-11 at%, P: 3-5 at%, Cu: 0.5-1.1 at%, C: 0-2 at%), achieves the desired balance between manufacturability and composition control complexity.

Inventive Principle:
Principle #35Parameter changes

Data Source

PatentEP3170586B1Alloy powder and magnetic component
Publication Date: 2020.01.01 TOHOKU MAGNET INST CO LTD

AI summary

Alloy powder of a composition formula Fe100-a-b-c-d-e-fCoaBbSicPdCueCf having an amorphous phase as a main phase is provided. Parameters satisfy the following conditions: 3.5 ≤ a ≤4.5 at%, 6 ≤ b ≤ 15 at%, 2 ≤ c ≤ 11 at%, 3 ≤ d ≤ 5 at%, 0.5 ≤ e ≤ 1.1 at%, and 0 ≤ f ≤ 2 at%. With this composition, the alloy powder has good magnetic characteristics even when it has a large particle diameter such as 90 µm. Therefore, yield thereof is improved.