Dynamic Induction Welding with Magnetic Shielding for Composite Joints
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing methods for welding composite materials with thermoplastic polymer matrices, such as those used in the aeronautics and automotive sectors, face challenges when one part is adjacent to a lightning protection system, as induction heating can lead to overheating of the protection system rather than achieving the necessary temperature for welding.
Innovation Solution
A dynamic induction welding installation with an induction heating device and a support that creates a reaction magnetic field to oppose the heating device's magnetic field, reducing induced currents and heat in the lightning protection system, allowing for efficient welding of composite parts without damaging the protection system.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Temperature
If induction heating is used to weld composite parts, then welding temperature at the interface is achieved, but the lightning protection system overheats
Solution Approach 1:
A magnetic shield composed of ferromagnetic material is introduced as an intermediary element positioned between the induction heating device and the lightning protection system. This shield redirects and concentrates the magnetic flux toward the welding interface while preventing excessive magnetic field penetration into the lightning protection system, thereby avoiding its overheating while maintaining effective heating at the weld zone
Solution Approach 2:
The magnetic shield is strategically positioned and dimensioned to create localized magnetic field concentration precisely at the welding interface between the two composite parts. By optimizing the shield's geometry and material properties, the magnetic flux is focused only where needed for welding, while areas adjacent to the lightning protection system experience reduced magnetic field intensity, preventing unwanted heating
2Strength
If autoclave consolidation is used to join parts, then mechanical properties are maintained, but treatment time and energy consumption increase
Solution Approach 1:
The mechanical consolidation process of autoclaving is replaced with induction heating that directly melts and welds the thermoplastic polymer matrix at the interface between composite parts. This substitution eliminates the need for prolonged autoclave treatment while achieving equivalent or superior joint strength through controlled localized heating and welding
Solution Approach 2:
The induction heating process utilizes controlled phase transition of the thermoplastic polymer matrix from solid to molten state at the welding interface. By precisely controlling the heating to achieve melting only at the interface, the parts are welded together rapidly, avoiding the lengthy autoclave consolidation time while maintaining mechanical integrity
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 solution effectively reduces the heating of the lightning protection system by up to 90% while achieving the necessary temperature for welding, thus preserving the mechanical properties of the parts and reducing energy consumption compared to autoclave methods.
Implementation Method 1
The use of an induction heating process using an inductor makes it possible to correctly increase the temperature at the interface between the two parts
Implementation Method 2
an induction heating device, which is disposed on a side of the first part that is opposite the second part and is configured to create a magnetic field
Implementation Method 3
a support disposed in contact with the lightning protection system on a side thereof that is opposite the second part, the support being configured to make it possible to create a reaction magnetic field at least partially opposing the magnetic field created by the induction heating device
Implementation Method 4
the interface between the parts where the weld is to be produced is brought to a temperature allowing the two parts to melt at this interface
Data Source
AI summary
A dynamic induction welding installation for welding first and second workpieces in a weld zone (S), the second workpiece being placed between a lightning protection system and the first workpiece, the workpieces including a composite material, the installation having an induction heating device placed on one side of the first workpiece facing away from the second workpiece and configured to create a magnetic field (Bi) so as to form the weld in the weld zone (S), and a medium placed in contact with the lightning protection system on a side opposite to the second workpiece, the medium being configured so as to be capable of generating a reaction magnetic field (B2) at least partially opposing the magnetic field (B1) in at least a part of the lightning protection system.