Removable Support-Layer Tape Structure for Thin-Ply AFP
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Automated fiber placement methods face challenges in processing thin-ply carbon fiber reinforced plastics (CFRP) tapes, particularly in cryogenic environments, due to issues such as curling, flipping, and edge quality impairment, which lead to microcracking and reduced laminate homogeneity.
Innovation Solution
A tape structure comprising a removable support layer and a fiber-reinforced layer, where the support layer prevents curling and edge impairment during processing, allowing for precise placement and handling of thin-ply tapes with sticky resins, and a fiber placement device with integrated peeling and winding mechanisms to maintain laminate quality.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If thin-ply CFRP tapes with layer thickness of less than 100 μm are used to prevent microcracking in cryogenic environments, then the resistance to microcracking is improved, but the tapes become very sensitive to processing damage such as curling, flipping, and edge quality impairment
Solution Approach 1:
A support layer is introduced as an intermediary element between the thin-ply CFRP tape and the processing environment. This support layer provides mechanical stability during handling and processing, preventing curling, flipping, and edge damage, while being removable after placement to leave the thin-ply tape intact on the composite structure.
Solution Approach 2:
The tape structure is segmented into two functional parts: a thin-ply CFRP layer for structural performance and microcracking resistance, and a separate support layer for processing stability. This segmentation allows each layer to perform its specific function optimally without compromising the other.
2Reliability
If multiple thin layers are used instead of thicker layers to prevent microcracking in cryogenic environments, then the resistance to microcracking is improved, but the laminate homogeneity deteriorates due to gaps, overlays, and ondulations
Solution Approach 1:
The support layer acts as a mediator that maintains laminate homogeneity by preventing gaps, overlays, and ondulations during the placement of multiple thin-ply layers. It ensures precise positioning and flat contact between layers, which is critical for achieving homogeneous laminates from sensitive thin-ply materials.
3Ease of operation
If standard aerospace prepreg materials with layer thickness of 125 to 250 μm are used, then the ease of processing is improved, but the resistance to microcracking in cryogenic environments deteriorates
Solution Approach 1:
The support layer compensates for the processing difficulties of thin-ply materials by providing the mechanical stability and handling characteristics similar to standard thicker prepregs. This allows the use of thin-ply CFRP tapes (less than 100 μm) that offer superior cryogenic performance without sacrificing ease of processing.
Data Source
Figure 1a~2
Figure 3
Figure 4
AI summary
The present invention provides a tape structure (102) for use in automated fiber placement (AFP) method to manufacture a composite structure (100), the tape structure (102) comprising a first layer (111) and a second layer (112) connected to the first layer (111) with the first layer (111) being configured as a support layer and the second layer (112) being configured as a pre-impregnated layer, wherein the first layer (111) is removable from the second layer (112) during or after placement of the second layer (112) on the composite structure (100) to be manufactured, an automated fiber placement device (130) an automated fiber placement (AFP) method and a composite structure (100) manufactured in the method.