Adhesives are used in a wide variety of engineering projects, and there is a huge range of adhesives to choose from. Choosing the right adhesive for a job can often be a critical decision that can result in the success or utter failure of a project, or as in the above example, life or death.
Understanding the requirements for a specific application is necessary to select the right adhesive for the job. There are a variety of requirements that an application that may be critical, as outlined in the following sections.
Strength of Bond
As described in the example above, sometimes strength of bond is the most critical characteristic in choosing an adhesive. Depending on how the load is applied to the bond, the factor to look for in an adhesive is either tensile strength or shear strength.
Stiffness or Flexibility of Bond
For some applications, a bond needs to be extremely stiff to maintain positioning, or on the other hand, very flexible to withstand strains in operation. For many applications, including strain gauge applications, the level of stiffness required in the adhesive depends on the levels of expected strain. If this characteristic is the primary constraint in the application, look at the Young’s modulus (E) for the adhesive.
