15 April 2014
15 April 2014
Huntsman Advanced Materials is offering free advice to designers and design engineers looking to achieve the best performance from adhesive bonding, focused on the importance of designing components for bonding as a recommended alternative to simply taking a design made for mechanical fastening.
According to Huntsman, in many application areas, industrial adhesives have superseded mechanical joining as the assembly technique of choice with their ability to provide outstanding lap shear strength, reduced corrosion, less finishing operations, reduced assembly costs, improved product performance, durability and greater design freedom.
It explains, high performance adhesives harden through a chemical reaction and have a strong affinity to joint surfaces. However, in order to maximise these inherent advantages, joints need to be designed and pre-treated in accordance with the adhesive selected and the application performance requirements.
As general guidelines for optimising bonding performance, Huntsman advises its customers to consider three essential factors; pre and post-application treatment and the loading conditions that bonded joints are subject to.
In the pre and post-application treatment, it says methods of application of the adhesive and the assembly of the components should always be taken into account at the design stage. In order to get the best performance from an adhesive bond, it is important to design the component for bonding rather than simply taking a design made for mechanical fastening. Together with the practical curing conditions, these determine the choice of adhesive type to be used.
Whilst considering loading conditions, bonded assemblies may be subject to tensile, compressive, shear or peel stresses, or a combination thereof. Adhesives are more resilient under shear, compression and tension stresses, performing less effectively under peel and cleavage loading. A bonded joint needs to be designed so that the loading stresses will be directed along the lines of the adhesive’s greatest strengths.