Ferrite Sintered Magnet Composition for High Magnetic Characteristics
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current ferrite sintered magnets face challenges in achieving high residual magnetic flux density (Br) and coercivity (HcJ) while maintaining good formability, as improving one characteristic often compromises the other.
Innovation Solution
A ferrite sintered magnet with a composition of Ca1-w-xLaAxFezComMnaO19, where w, x, z, m, and a satisfy specific atomic ratio ranges, and optionally containing SiO2 and Cr2O3, to achieve high Br, HcJ, and formability.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If element combinations are changed to improve magnetic characteristics (Br and HcJ), then magnetic performance increases, but formability deteriorates
Solution Approach 1:
The patent applies parameter changes by precisely controlling the atomic ratios of multiple elements (Ca, La, Sr, Ba, Fe, Co, Mn) within specific ranges. The composition formula Ca1-w-xLawAxFezComMnaO19 with constrained parameters (0.21≤w≤0.62, 0.02≤x≤0.46, 7.43≤z≤11.03, 0.18≤m≤0.41, 0.046≤a≤0.188) enables optimization of magnetic properties while maintaining formability through systematic parameter adjustment rather than arbitrary element addition
Solution Approach 2:
The patent employs composite materials by combining multiple ferrite-forming elements (Ca, La, Sr, Ba) with transition metal elements (Fe, Co, Mn) in a controlled composition. This multi-element composite approach creates a synergistic effect where the combination of specific elements in defined proportions achieves both high magnetic characteristics and good formability, resolving the trade-off between these properties
2Reliability
If Br and HcJ are increased through element addition, then magnetic characteristics improve, but Hk/HcJ ratio decreases
Solution Approach 1:
The patent uses parameter changes to simultaneously optimize Br, HcJ, and Hk/HcJ ratio by controlling the atomic ratios within the composition formula. The specific parameter ranges (particularly the constrained ratios of Co and Mn relative to Fe, and the controlled addition of La and rare earth elements) create a balanced magnetic structure that maintains high squareness ratio while achieving high magnetic characteristics
Data Source
AI summary
A ferrite sintered magnet includes a composition expressed by a formula (1) of Ca1-w-xLawAxFezComMnaO19. In the formula (1), “w”, “x”, “z”, “m”, and “a” satisfy a formula (2) of 0.21≤w≤0.62, a formula (3) of 0.02≤x≤0.46, a formula (4) of 7.43≤z≤11.03, a formula (5) of 0.18≤m≤0.41, and a formula (6) of 0.046≤a≤0.188. In the formula (1), “A” is at least one kind of element selected from a group consisting of Sr and Ba.