Magnetic Iron Oxide Rubber Sheet for Millimeter-Wave Absorption
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current electromagnetic-wave absorbing sheets lack elasticity and effectiveness in absorbing high-frequency electromagnetic waves above the millimeter-wave band, limiting their ability to shield electromagnetic waves in complex or curved environments.
Innovation Solution
An electromagnetic-wave absorbing sheet with a magnetic iron oxide that magnetically resonates in the high-frequency band, combined with a rubber binder, providing a maximum elongation percentage of 20% to 200% in the in-plane direction, allowing for flexible arrangement and effective absorption of electromagnetic waves up to several tens of GHz.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Adaptability or versatility
If electromagnetic-wave absorbing sheets use conventional materials (carbon nanotubes, silicon carbide, metal powders), then they can provide electromagnetic wave absorption in certain frequency bands, but they lack elasticity and cannot achieve elongation of 20% or more in the in-plane direction
Solution Approach 1:
The patent uses a composite material system consisting of magnetic iron oxide particles (epsilon phase or hexagonal phase) dispersed in a rubber binder matrix. This composite structure allows the material to simultaneously exhibit the electromagnetic wave absorption properties of magnetic iron oxide and the elastic deformability of rubber, achieving both high elongation capability (20-200%) and effective electromagnetic wave absorption in the millimeter-wave band and higher frequency ranges.
2Reliability
If electromagnetic-wave absorbing sheets are designed to absorb high-frequency electromagnetic waves (millimeter-wave band and above), then they can provide shielding for modern communication systems, but they become rigid and lose flexibility for conformal mounting on curved surfaces
Solution Approach 1:
The patent changes the physical state and compositional parameters of the absorbing material by using fine magnetic iron oxide particles (average particle size 0.1-10 μm) dispersed in a rubber binder. This parameter change transforms the material from a rigid structure to a flexible composite that can be elongated by 20% or more while maintaining its electromagnetic wave absorption effectiveness in the millimeter-wave band and higher frequencies through magnetic resonance mechanisms.
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 sheet effectively converts high-frequency electromagnetic waves into heat, offering high electromagnetic-wave absorption properties while maintaining flexibility and ease of handling, even on curved surfaces, thereby enhancing electromagnetic-wave shielding capabilities.
Implementation Method 1
an electromagnetic-wave absorbing layer that contains a magnetic iron oxide that magnetically resonates in a frequency band equal to or higher than a millimeter-wave band as an electromagnetic-wave absorbing material
Data Source
Figure 1
Figure 2
Figure 3A~3B
AI summary
Provided is an electromagnetic-wave absorbing sheet that can favorably absorb electromagnetic waves of high frequencies in a frequency band equal to or higher than the millimeter-wave band while having elasticity of elongating in an in-plane direction. The electromagnetic-wave absorbing sheet includes an electromagnetic-wave absorbing layer 1 that contains a magnetic iron oxide 1a that magnetically resonates in a frequency band equal to or higher than the millimeter-wave band as an electromagnetic-wave absorbing material and a rubber binder 1b. The electromagnetic-wave absorbing sheet has a maximum elongation percentage of an elastic region in one in-plane direction of 20% to 200%.