Stepped Ply Overlap Fusion for Strong Thermoplastic Composite Joints
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The widespread adoption of thermoplastic composites in industries like the aircraft industry is limited due to challenges in manufacturing and repairing methods, which often result in joints with reduced structural strength, failing to meet industry requirements for safety, airworthiness, and fast throughput.
Innovation Solution
A method for joining thermoplastic composite components involves forming a joint region with a stepped arrangement where material plies overlap at varying distances, followed by applying elevated temperature and pressure to fuse the components, accommodating zones with different numbers of plies.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of manufacture
If mechanical fasteners such as bolts and nuts are used to join thermoplastic components, then the components can be easily assembled, but the joint structural strength is reduced
Solution Approach 1:
The patent replaces mechanical fastening systems (bolts, nuts, rivets) with a thermal joining process that uses elevated temperature and pressure to fuse thermoplastic composite components together. This substitution eliminates the need for mechanical fasteners while creating stronger, more integrated joints through material fusion, directly resolving the contradiction between ease of assembly and joint strength.
Solution Approach 2:
The patent changes the physical parameters of the thermoplastic material by applying elevated temperature (approaching melting point) and pressure during the joining process. This parameter change transforms the material state to enable direct fusion of components, creating strong joints without mechanical fasteners and improving both joint strength and manufacturing efficiency.
2Ease of manufacture
If traditional joining methods are used for thermoplastic components, then the manufacturing process is simple, but the production throughput is insufficient to meet industry requirements
Solution Approach 1:
The patent applies elevated temperature and pressure parameters to the thermoplastic composite components, enabling rapid fusion and significantly reducing joining time. This parameter change allows the manufacturing process to achieve high production throughput while maintaining simplicity, as the process can be automated and performed in a single operation without complex assembly steps.
Solution Approach 2:
The patent utilizes the phase transition of thermoplastic materials by heating them to near melting point during the joining process. This phase transition enables the material to become sufficiently pliable for fusion, allowing rapid joining operations that increase production throughput while keeping the process relatively simple and controllable.
3Ease of manufacture
If thermoplastic composite components are joined with reduced structural strength, then manufacturing costs are lower, but safety and airworthiness requirements are not met
Solution Approach 1:
The patent replaces mechanical fastening systems with thermal fusion joining, creating joints with superior structural strength that meet safety and airworthiness requirements. This substitution eliminates the stress concentrations and potential failure points associated with mechanical fasteners, thereby improving reliability while maintaining manufacturing efficiency and cost-effectiveness.
Solution Approach 2:
The patent utilizes the properties of thermoplastic composite materials by heating them to near melting point to enable fusion joining. This approach leverages the inherent strength and integrity of the composite materials themselves to create strong, reliable joints that meet safety requirements, rather than relying on separate mechanical fastening systems that could compromise structural 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
This approach enhances structural strength and efficiency in joining thermoplastic components, supporting increased production rates and meeting industry standards for safety and throughput.
Implementation Method 1
The elevated temperature and elevated pressure joining process may include elevating the components to a temperature and pressure at, or close to, a melting point of thermoplastic material of the FTC and/or STC component
Implementation Method 2
joining the FTC and STC components by applying an elevated temperature and an elevated pressure to the FTC and STC components within the joint region
Data Source
Figure 1~2
Figure 3~3A
Figure 4
AI summary
A method for joining thermoplastic composite components (20A, 20B) is provided that includes: providing a first thermoplastic composite (FTC) component (20A) having an FTC first zone and an FTC second zone; providing a second thermoplastic composite (STC) component (20B) having an STC first zone and an FTC second zone; forming a joint region (26) between the FTC and STC components (20A, 20B) by disposing them in a stepped arrangement, wherein each material ply (22) within the FTC first zone overlaps a material ply (22) within the STC first zone by a first overlap distance (X), and at least one material ply (22) within the FTC second zone overlaps a material ply (22) within the STC second zone by a second overlap distance (X), and at least one material ply (22) within the FTC second zone overlaps a material ply (22) within the STC second zone by the first overlap distance (X); and joining the FTC and STC components (20A, 20B) by applying an elevated temperature and pressure.