CCT CCT Surface Preparation & Bonding 2

Question 1

What adhesive form is most often used for structural composite bonding in aerospace applications?

Accepted Answer

Film adhesive (e.g., Redux or EA9696)

Answer

Film adhesives provide uniform bondline thickness and consistent mechanical properties critical for aerospace structures.

Question 2

What is bondline thickness, and why is it controlled during adhesive bonding?

Accepted Answer

The cured adhesive gap between adherends; controlled to ensure designed strength and prevent starved or thick bonds

Answer

Too thin a bondline (starved) reduces strength, while too thick reduces stiffness and increases void content.

Question 3

What is the function of a bond fixture or tooling during adhesive cure?

Accepted Answer

To maintain part geometry and apply uniform pressure during cure

Answer

Bond fixtures hold mating parts in alignment and apply the clamping pressure needed for proper adhesive flow and cure.

Question 4

During a co-bond operation, what is being joined?

Accepted Answer

A cured laminate to an uncured laminate using adhesive, cured simultaneously

Answer

In co-bonding, one part is already cured and the other (with or without film adhesive) is cured in the same cycle.

Question 5

What type of failure mode indicates that the adhesive was stronger than the surface preparation?

Accepted Answer

Adhesive failure at the bondline interface

Answer

Adhesive (interfacial) failure means the adhesive separated from the substrate surface, indicating poor surface prep.

CCT - Certified Composite Technician Practice Test