With knowledge on the likely service requirements of your joint established, the detailed design can then be undertaken. Basic design does not have to involve complex calculations, since the approximate joint sizing can be determined by ensuring the principal stresses within the adhesive or adherends do not exceed the elastic limit of the chosen materials, or a value based on a chosen safety margin. Design diagrams may be developed on this basis for particular adhesive systems so that design choices can be made for particular loading requirements in terms of joint type, substrate thickness, overlap length etc.
The process may involve some or all of the following accounting for strength, creep, fatigue, impact and environmental factors as required.
- Choice of joint type.
- Basic sizing calculations using approximate analytical methods.
- Detailed analysis using finite element analysis (FEA).
This design criteria module provides an overview to design of adhesive joints, including typical stress distributions found in model joints, general practices for improving joint strength and longevity, and the application of both fracture mechanics and FEA to both optimise joint design and assess joint life.
Where appropriate, links are provided to more detailed tools within the Adhesives Toolkit that address design issues.
