Composite Sandwich Structure Welding for High-Temperature Bonding
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Composite sandwich structures used in aerospace applications face challenges with braze joints degrading and failing at high temperatures, leading to potential structural failures.
Innovation Solution
The method involves positioning supports between metallic substrates and an undulating core member, welding the core member to the substrates, and then removing the supports using thermal or chemical processes, allowing for robust bonding without the limitations of traditional braze joints.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Temperature
If traditional braze joints are used to bond substrates to core support structure, then bonding is achieved at lower temperatures, but the joints degrade and fail at high temperatures
Solution Approach 1:
The patent changes the bonding method from brazing to welding, fundamentally altering the joining process parameters. Welding creates metallurgical bonds that maintain strength at high temperatures, unlike braze joints that rely on filler metals with lower melting points. This parameter change enables the composite structure to withstand temperatures above 1000°C while maintaining bonding reliability.
Solution Approach 2:
The patent replaces the mechanical/thermal brazing process with an electromagnetic welding process. Instead of using filler metals and controlled thermal cycles characteristic of brazing, the invention employs welding techniques (such as laser welding or electron beam welding) that create direct metallurgical bonds between dissimilar metals, eliminating the temperature limitation inherent in braze joints.
2Temperature
If welding is used to bond substrates to core support structure, then high temperature resistance is achieved, but material distortion and warping may occur
Solution Approach 1:
The patent segments the bonding process into multiple localized welding zones rather than attempting to weld the entire structure at once. By dividing the bonding area into discrete segments that can be welded sequentially or simultaneously at different locations, the thermal input is distributed and controlled, preventing cumulative heat distortion while achieving complete bonding across the dissimilar metal interface.
Solution Approach 2:
The patent employs dynamic welding parameters that can be adjusted in real-time during the bonding process. Welding speed, power input, and travel path are dynamically controlled based on feedback from the bonding process, allowing the system to adapt to varying thermal conditions and minimize distortion. This dynamic control enables high temperature resistance while maintaining dimensional stability.
3Strength
If dissimilar metals are welded together, then high temperature bonding strength is achieved, but process complexity increases
Solution Approach 1:
The patent introduces an intermediary transition layer or intermediate material between the dissimilar metals that facilitates welding. This intermediate layer acts as a mediator that is compatible with both base metals, enabling the welding process to proceed with standard techniques while achieving strong metallurgical bonds. The intermediary layer simplifies the overall process by eliminating the need for highly specialized dissimilar metal welding procedures.
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 the structural integrity and thermal resistance of composite sandwich structures by maintaining bonding strength even at high temperatures, while also reducing material weight.
Implementation Method 1
welding the first peak to the first surface of the first metallic substrate in an area of the first support
Implementation Method 2
removing the first support by at least one of a thermal removal process or a chemical removal process
Data Source
AI summary
In some examples, a technique including positioning supports such that the supports are between a first metallic substrate and a second metallic substrate, wherein an undulating member is located between the first metallic substrate and the second metallic substrate, the undulating member defining a plurality of first peaks adjacent to a first surface of the first metallic substrate and a plurality of second peaks adjacent to a second surface of the second metallic substrate, wherein a first support of the supports is positioned such that the first support extends between a first peak of the plurality of first peaks and the second surface of the second metallic substrate; welding the first peak to the first surface of the first metallic substrate in an area of the first support; and removing the first support by at least one of a thermal removal process or a chemical removal process.