What is the primary purpose of creating a surface profile during surface preparation?

• A. To change color of coating.
• B. To improve coating adhesion by providing a mechanical key.
• C. To increase rust formation.
• D. To remove all moisture.

Answer: (B)

Creating a surface profile roughens the substrate so the coating can form a mechanical bond. The rough texture provides interlocking grooves and peaks that the coating material grips as it cures, increasing adhesion and helping prevent delamination under service conditions. This step goes hand in hand with cleaning to ensure the coating bonds to a clean, rough surface rather than a smooth, contaminated one. Color change is cosmetic, increasing rust would indicate poor prep, and removing moisture is a separate drying step; the profile itself is about creating a grip for the coating.