What does adhesive failure signify in a bonding process?

Adhesive failure indicates that the failure occurs at the interface between the adhesive and one of the adherents, rather than within the material of the adherends themselves. This type of failure signifies that the bonding agent (adhesive) has not successfully adhered to either surface, leading to a separation or delamination at that specific point.

In contexts of bonding processes, achieving a strong bond is crucial for the integrity of the assembly. If adhesive failure occurs, it often means that factors such as surface contamination, improper application of the adhesive, or inadequate curing conditions have prevented the adhesive from forming a strong molecular bond with the surface. This understanding is fundamental in engineering practices, as it guides improvements in joint design and material selection to enhance the overall effectiveness of bonding techniques.