Surface-Opened Prepreg Structure for Faster Composite Debulking
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Fiber-reinforced polymer composites face challenges in removing trapped gases during consolidation, leading to porosity and reduced mechanical properties due to the matrix resin inhibiting gas movement, which prolongs debulk time and increases costs.
Innovation Solution
Curable prepregs with surface openings created by thermal treatment of woven fabrics allow for enhanced gas removal by forming pockets and channels, facilitating faster debulking and reduced porosity in the final composite.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Productivity
If traditional prepregs without surface openings are used, then the structure is simple and easy to manufacture, but gases are trapped inside and between prepreg layers resulting in porosity and extended debulk time
Solution Approach 1:
The prepreg is designed with a porous structure featuring surface openings that penetrate through the resin matrix to expose fiber reinforcement. This porous architecture creates gas escape pathways, enabling trapped gases to vent during consolidation without requiring extended debulk times. The controlled porosity is achieved through specific manufacturing processes that create interconnected void spaces while maintaining structural integrity.
Solution Approach 2:
The continuous resin matrix is segmented by creating discrete surface openings and internal pore channels. These segmented pathways divide the gas removal function into multiple distributed escape routes across the prepreg surface, allowing gases to exit at numerous locations simultaneously rather than requiring a single complex vacuum system.
2Manufacturing precision
If traditional prepregs without surface openings are used, then manufacturing is simpler, but porosity increases due to trapped gases inhibiting consolidation
Solution Approach 1:
The prepreg incorporates a controlled porous structure with surface openings that provide dedicated gas escape pathways. This design enables precise control over porosity by regulating the size, distribution, and connectivity of the pore network during manufacturing, ensuring optimal gas removal while maintaining structural performance.
Solution Approach 2:
Gas entrapment is addressed by extracting the gas removal function from the consolidation process itself and providing dedicated escape pathways through surface openings. This separates the gas venting function from the densification function, allowing each to be optimized independently.
3Productivity
If edge breathers are used to remove gases, then some gas removal is achieved, but the process is slow and cannot substantially remove all trapped gases
Solution Approach 1:
Gas removal transitions from a one-dimensional edge-based process to a two-dimensional surface-wide process. Surface openings distributed across the entire prepreg top surface create multiple exit points, transforming the gas removal geometry from edge-only to surface-wide, dramatically increasing the effective gas escape area and rate.
Solution Approach 2:
The gas removal function is segmented into multiple distributed pathways through surface openings rather than relying on a single edge breather system. This segmentation creates parallel gas escape routes that operate simultaneously, multiplying the overall gas removal capacity.
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 use of surface openings in prepregs significantly reduces debulk time and porosity in composite materials, enhancing mechanical properties and efficiency in composite fabrication.
Implementation Method 1
Each curable prepreg is a resin-impregnated, woven fabric that has been thermally treated to create an array of openings in at least one major surface
Data Source
AI summary
Curable prepregs possessing enhanced ability for the removal of gases from within prepregs and between prepreg plies in a prepreg layup prior to and/or during consolidation and curing. Each curable prepreg is a resin-impregnated, woven fabric that has been subjected to a treatment to create an array of openings in at least one major surface. The location of the openings is specific to the weave pattern of the fabric. Furthermore, when these prepregs are laid up and subjected to a debulking process to form a composite part, a shorter debulking time can be achieved as compared to using prepregs without the same surface openings.