Flexible Pressurization for Pore-Free Thermoplastic Composite Welding
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing methods for thermally joining thermoplastic fiber composite components often result in porosity due to air infiltration and require complex, costly clamping molds that are difficult to apply uniformly, especially in hard-to-reach areas.
Innovation Solution
A method and apparatus using a flexible pressurization arrangement that applies and maintains pressure on the components during and after welding, preventing air infiltration and eliminating the need for fixed clamping molds by employing a flexible cover that can be electrically conductive, insulating, or permeable as needed for different welding techniques.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Stress or pressure
If fixed clamping molds are used to apply pressure during welding, then pressure can be maintained, but the device complexity and cost increase significantly
Solution Approach 1:
The patent employs a flexible pressurization arrangement consisting of a pressurizable membrane or flexible pressurization device that can be inflated or expanded to apply and maintain pressure on the thermoplastic fiber composite components during and after welding. This flexible approach replaces complex fixed clamping molds while achieving the same pressure maintenance function through pneumatic or hydraulic inflation of the membrane structure.
2Reliability
If fixed clamping molds are used to prevent air infiltration, then joint quality improves, but the ease of operation and adaptability decrease
Solution Approach 1:
The flexible pressurizable membrane can be easily positioned and adapted to various component geometries and hard-to-reach welding locations. The membrane's flexibility allows it to conform to complex shapes and access areas where rigid clamping molds would be difficult or impossible to apply, while still maintaining the pressure necessary to prevent air infiltration and ensure high joint quality.
Solution Approach 2:
The pressurization system transitions from a static fixed mold to a dynamic flexible membrane that can be inflated and deflated as needed. This dynamic approach allows the membrane to adapt its shape and pressure application to different welding scenarios and locations, improving ease of operation and adaptability while maintaining reliable pressure for pore-free joints.
3Loss of time
If pressure is released immediately after welding, then the process time is reduced, but porosity forms due to air infiltration
Solution Approach 1:
The flexible membrane is inflated and pressure is applied in advance before welding begins, and the pressure is maintained continuously through the welding process and into the cooling phase. This preliminary and sustained pressure application prevents air from infiltrating the joint zone as the thermoplastic matrix solidifies, ensuring pore-free joints while allowing the welding operation itself to proceed efficiently without unnecessary delays.
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 approach ensures a strong, pore-free joint by maintaining pressure until the matrix solidifies, simplifies the welding process, and reduces the complexity and cost of equipment, particularly benefiting applications like aircraft assembly.
Implementation Method 1
extensive pressurization of thermoplastic fiber composite components to be joined by the pressurization arrangement, with the result that the fiber composite components are pressed against one another, at least in the joining zone
Implementation Method 2
welding the fiber composite components in the joining zone during pressurization
Implementation Method 3
maintaining the pressurization by the pressurization arrangement until the joining zone solidifies
Data Source
AI summary
An apparatus for thermally joining thermoplastic fiber composite components includes a pressurization arrangement for jointly covering, at least in a region of a joining zone, thermoplastic fiber composite components to be joined and applying pressure to the thermoplastic fiber composite components to press the thermoplastic fiber composite components against one another, at least in the joining zone, the pressurization arrangement being flexible, at least in some section or sections. A welding device is configured for welding the fiber composite components in the joining zone during pressurization. The pressurization arrangement and welding device are configured to weld the thermoplastic fiber composite components in a pressurized state in the joining zone. The pressurization arrangement is configured to maintain pressurization independently of the welding device until the joining zone solidifies. A cover is also disclosed for a pressurization device for thermally joining thermoplastic fiber composite components.