Magnetostrictive Wire Bond Strength Detection
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing methods for measuring bond strength in composite materials are often destructive and impractical, especially in complex structures where access is limited, and cannot accurately detect smaller defects like gaps or contamination issues.
Innovation Solution
Incorporating ferro-magnetic and magnetostrictive wires into the adhesive between layers of composite materials, which respond to a magnetic field by changing stress levels, allowing for non-destructive testing through monitoring magnetic and acoustic responses to determine bond quality.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If destructive pull testing is used to measure bond strength, then accurate bond strength data can be obtained, but the material is damaged and the method is impractical for complex structures
Solution Approach 1:
The patent replaces the mechanical pull-testing system with a magnetic field-based sensing system. Magnetostrictive wires embedded in the adhesive layer respond to applied magnetic fields by changing their magnetic properties based on the stress state, allowing bond strength measurement without mechanical contact or destruction of the bonded joint.
Solution Approach 2:
The patent introduces magnetostrictive wires as intermediary elements within the adhesive layer. These wires act as sensors that translate mechanical stress in the bond into detectable magnetic signal changes, enabling indirect measurement of bond strength without direct mechanical testing of the joint itself.
2Reliability
If mechanical fasteners are used to ensure robust bonding, then bond reliability is improved, but the structure becomes heavier and more complex
Solution Approach 1:
The patent enables the adhesive-bonded joint to self-verify its own integrity through the embedded magnetostrictive wires. The sensing capability is built into the bond itself, allowing the structure to monitor its own bond health without requiring additional external sensing systems or mechanical fasteners for verification.
3Ease of manufacture
If traditional testing methods are used, then manufacturing process is simple, but small defects like contamination or uneven adhesion cannot be detected
Solution Approach 1:
The patent implements local sensing capability by embedding magnetostrictive wires directly within the adhesive layer at critical locations. This allows localized detection of bond quality and small defects such as contamination or uneven adhesion at specific points within the bond line, rather than only overall bond strength measurement.
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
Enables the detection of defects and assessment of bond strength without damaging the material, providing a reliable method to identify areas with weak or defective bonding, even in small or hard-to-reach areas, thereby improving the integrity and design of composite materials.
Implementation Method 1
The adhesive may include a plurality of ferro-magnetic wires
Implementation Method 2
Each of the plurality of wires may be ferro-magnetic and magnetostrictive
Data Source
AI summary
A tester for bonded composite materials uses a magnetic source to generate a response signal from wires infused in an adhesive used between layers of the composite material. Acoustic or magnetic response signals, separately or in combination, can be received and analyzed to detect stresses in wires indicative of voids in the adhesive or other defects affecting the bond quality between layers of the composite material.