Spring Fixture for High Temperature Brazing Distortion
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
In high temperature brazing and diffusion bonding, existing fixtures face challenges in controlling pressure to prevent component deformation and distortion, while also maintaining tooling life and reducing residual loads.
Innovation Solution
A fixture comprising springs with constant stress, alloy pressure pads, and supports that achieve force and moment equilibrium, allowing for efficient assembly and minimizing distortion by using springs to press components together as the filler metal melts.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Force
If conventional fixtures are used to apply pressure during high temperature brazing, then components can be joined, but the components may be overly deformed due to uncontrolled pressure
Solution Approach 1:
The spring material properties are specifically selected and engineered to provide appropriate stiffness characteristics. By changing the material parameters and spring geometry, the fixture delivers controlled pressure that prevents component deformation while ensuring adequate contact between parts during brazing.
Solution Approach 2:
The fixture transitions from a static rigid structure to a dynamic system using springs that can adapt their pressure application. The springs provide progressive resistance to compression, automatically adjusting the pressure applied to components based on their thermal expansion and deformation characteristics during the heating process.
2Manufacturing precision
If high pressure is applied to prevent component deformation, then manufacturing precision is maintained, but residual loads must be reacted through outer alloy supports causing distortion
Solution Approach 1:
The fixture design distributes pressure application locally through multiple spring contact points rather than concentrating loads through outer supports. Each spring applies pressure locally at specific component interfaces, eliminating the need for residual loads to be reacted through distant alloy supports that would cause distortion.
Solution Approach 2:
The spring-based pressure application creates a more uniform pressure distribution across the component interfaces. By equating the pressure potential at multiple contact points through properly positioned springs, the system achieves equilibrium that prevents distortion without requiring compensating residual loads in the support structure.
3Force
If rigid pressure application is used to maintain force equilibrium, then components are held together, but tooling life is reduced due to stress concentrations
Solution Approach 1:
The spring elements act as flexible mechanical components that distribute stresses uniformly along their length. Unlike rigid pressure bars that create stress concentrations at contact points, the flexible springs deform gradually, spreading the mechanical load and reducing peak stresses that would otherwise reduce tooling life.
Solution Approach 2:
The springs provide a cushioning effect by absorbing and distributing impact and thermal expansion forces before they can concentrate on critical fixture components. This beforehand cushioning through elastic deformation protects the tooling from high-stress events during the brazing process.
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 solution effectively reduces component distortion, improves tooling life, and eliminates the need for residual loads, ensuring precise bonding and extended fixture durability.
Implementation Method 1
The springs may be designed and manufactured such that the spring possesses constant stress throughout the spring, which may provide high strain for a given load
Implementation Method 2
a plurality of alloy pressure pads shaped to contact a component to be brazed or diffusion bonded
Implementation Method 3
In high temperature brazing, two components may be joined by applying pressure between the two components and heating the components slightly above the melting point of a filler metal
Implementation Method 4
In diffusion bonding, the springs may be used to press the parts of the component together while heating the component
Data Source
AI summary
A fixture may include a plurality of alloy pressure pads shaped to contact a component to be brazed or diffusion bonded, a plurality of springs, and at least one alloy support. In some examples, each spring of the plurality of springs is shaped to have a substantially constant stress throughout the spring. The plurality of springs may be between and contacting the at least one alloy support and the plurality of alloy pressure pads to exert spring forces on the plurality of alloy pressure pads. In some examples, the plurality of springs include a plurality of silicon nitride springs.