Why is it Important to Remove Corrosion Prior to Applying Coatings
There are several reasons why coatings can fail on a metal part, but leading the top of the list is a poorly prepared surface.
Corrosion Underneath the Coating: If the metal substrate is corroded before the coating is applied, the corrosion can continue beneath the coating. Over time, this can cause blistering, cracking, or delamination of the coating as the corrosion progresses. Proper surface preparation to remove corrosion is essential to prevent this issue.
Inadequate Surface Preparation: One of the primary causes of coating failure is improper surface preparation. If the metal surface is not thoroughly cleaned, degreased, and free from contaminants such as rust, oils, dirt, or scale, the coating may not adhere properly, leading to adhesion failure.
It is crucial to remove corrosion before applying a coating for several reasons:
- Adhesion: Corrosion typically forms a layer of oxides or other contaminants on the surface of the substrate. This layer acts as a barrier between the substrate and the coating, preventing proper adhesion. By removing corrosion, the clean substrate allows the coating to adhere effectively, ensuring better coating performance and durability.
- Coating Integrity: Corrosion can continue to progress under a coating, compromising its integrity. If the underlying corrosion is not removed, it can lead to blistering, peeling, or cracking of the coating, allowing moisture or chemicals to reach the substrate and accelerate corrosion. Properly preparing the surface by removing corrosion helps maintain the long-term effectiveness of the coating.
- Durability and Longevity: A coating’s ability to protect the substrate from corrosion is dependent on its adhesion and the absence of corrosion beneath it. By removing corrosion, the coating can fully bond to a clean and stable surface, enhancing its resistance to corrosion and extending its lifespan.
- Appearance: Corrosion often results in an unsightly appearance, with rust stains, pitting, or discoloration on the substrate. Removing corrosion improves the aesthetic appeal of the coated surface, providing a smooth and visually appealing finish.
- Performance and Functionality: Corrosion can compromise the performance and functionality of the substrate. For example, in the case of metal components, corrosion weakens the material, reduces structural integrity, and affects mechanical properties. Removing corrosion helps restore the substrate’s performance and functionality, allowing the coating to provide optimal protection.
Are you properly preparing your parts prior to coating to ensure the greatest success and quality of your parts? LS Industries can design a machine around your needs and applications to ensure you are getting the best finish possible. Let’s talk corrosion and a properly prepared surface.
Melissa Gibson (Palmer)
East Coast Sales