ADHESIVES, GLUES AND SEALANTS


Adhesive fractures - Types of fractures and explanations

Knowledge of different types of failures or fractures that have occurred in a bonded joint plus the use of analytical techniques, which allow us to know the origin and cause of the problem, in order to take remedial action if necessary.

Before to the description of the topology or failure modes of an adhesive bonding is necessary to define and understand the concepts of theoretical and real tensile strength:

Types of fractures - Failure Modes of adhesive bonding.

glue point Substrate fracture

Substrate fracture - There has been breaking the adhesive bonding in one of the two substrates.

In this type of fracture the σreal <σteórica

Possible origins and causes:

substrate fracture

glue point Adhesion fracture

Adhesion fracture - The adhesive bonding fracture has occurred in the area of adhesion between the adhesive and the substrate, in that type of fracture the adhesive is totally or partially separated from the substrate surface. The adhesion fracture can occur in the one and on both substrates and this type of fracture is not desirable.

In this type of fracture the σreal <σteórica

Possible origins and causes:

adhesion fracture

glue point Cohesion fracture

Cohesion fracture - The adhesive bonding fracture has occurred in the adhesive material itself; we can see traces of adhesive on both surfaces of the substrate.

Possible origins and causes:

When the adhesive σteorica ≈ σreal (This type of fracture is desirable.)

When σreal <σteorica. (This type of fracture is not desirable.)

cohesion fracture

glue point Hybrid fracture

The combination of the 3 main fracture types produces the following types of fractures:

hybrid fracture


If you like, share it




Advertisement