Ferromagnetic Core Impedance Measurement for Composite Fiber Density
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current non-destructive methods for evaluating the distribution and orientation of ferromagnetic, electrically conductive fibers in composite materials, such as steel-fibre-reinforced concrete, are limited in accurately determining density and homogeneity, and fail to provide precise information on fiber position and orientation.
Innovation Solution
A method utilizing a C, U, or E-shaped ferromagnetic core with adjustable frequency electric coils to measure complex impedance at various positions and angles, allowing for the evaluation of mass density and distribution homogeneity of ferromagnetic and electrically conductive fibers by setting the device to resonate at specific quality factors, enabling accurate density and volume calculations.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If non-destructive methods are used to evaluate fiber distribution, then the material structure is preserved, but the accuracy of determining density and homogeneity deteriorates
Solution Approach 1:
The patent changes the frequency parameter of the magnetic field to match the resonant frequency of the ferromagnetic fibers. By tuning the excitation frequency to the natural resonant frequency, the method achieves enhanced sensitivity and accurate measurement of fiber density and orientation without requiring material destruction
Solution Approach 2:
The patent utilizes magnetic resonance vibration by exciting the ferromagnetic fibers at their natural resonant frequency. The resonant oscillation of the magnetic moments provides a strong signal that enables precise non-destructive measurement of fiber distribution, density, and orientation parameters
2Reliability
If impedance spectroscopy is used to evaluate magnetic permeability, then non-destructive evaluation is achieved, but the ability to determine fiber density and orientation accurately deteriorates
Solution Approach 1:
The patent employs magnetic resonance by exciting the ferromagnetic fibers at their natural resonant frequency. This resonant excitation produces a strong, frequency-specific signal that enables accurate determination of fiber density, volume fraction, and orientation while maintaining non-destructive evaluation
Solution Approach 2:
The patent transitions from broadband impedance spectroscopy to frequency-selective resonant excitation. By changing the approach from evaluating magnetic permeability across a frequency range to targeting the specific resonant frequency of the fibers, the method achieves superior precision in measuring fiber distribution and orientation parameters
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
This method provides a reproducible and accurate evaluation of fiber density and orientation within a guaranteed scatter range, overcoming the limitations of existing methods by ensuring high sensitivity and applicability to various composite materials, including those in civil engineering and aerospace applications.
Implementation Method 1
setting the device to resonate at specific quality factors
Implementation Method 2
electric coils to measure complex impedance
Implementation Method 3
C, U, or E-shaped ferromagnetic core
Data Source
Figure 1a
Figure 1b
Figure 1c
AI summary
A method and a device for evaluating the distribution and orientation of ferromagnetic, electrically conductive fibres in a composite material are disclosed. The principle consists in repeatable evaluation of the density of ferromagnetic, electrically conductive fibres at the measured location, and such evaluation is performed within a guaranteed scatter range of the measured data and at a guaranteed accuracy rate. A device to perform the method comprises a C, U or E-shaped ferromagnetic core (1) with distributed or uniform winding of the electric coil (2), where the ferromagnetic core (1) exhibits dimensions A, B, and C, for which we have C≥3B and B≈A, where A denotes the width of an arm (1.2), B represents the depth of an arm (1.2), and C is the length of the base (1.1). The ferromagnetic core (1) is equipped with at least two electric coils (2) and, to ensure strong electromagnetic coupling on the ferromagnetic core (1), the winding of the electric coil (2) is configured on both arms of the ferromagnetic core (1). The leads of the electric coil (2) winding are, at the winding terminals (3), connected to an external electric circuit (17) including an electric voltage generator (16) with adjustable frequency f and a measuring device (18).