What Does Coating Failure Mean?
Coating failure is the reduction or loss of a coating's bond between coats and a substrate. This encompasses situations when it no longer protects the object's surface or substrate, does not look aesthetic or does not provide other functions.
Catastrophic coating failure is very sudden, dramatic and serious. A premature failure occurs significantly before the end of a coating's life expectancy.
Coating failures can occur for numerous reasons, but most are attributable to:
- Basic formulation design
- Incorrect system specifications
- Poor surface preparation
- Improper application
- Environmental stress factors
Coating failure can lead to weakened structures and eventually catastrophic failure. Therefore it is important to prevent coating failures.
Corrosionpedia Explains Coating Failure
Coating failures in industrial situations can be very costly, leading to premature deterioration and failure. Many times blame is placed on the coating materials when, in fact, many failures occur in situations where specifications for surface preparation, undercoating or coating application have not been prepared or are simply not followed.
For example, improper or incomplete cleaning and removal of rust or other surface contamination can lead to incomplete adhesion of the coating to the metal surface. Improper surface profile also limits the usefulness of a normally acceptable coating system. Insufficient curing between coats and improper mixing of multi-component systems can also cause failure.
To identify correct causes of coating failure, one must understand:
- Background information on the previously applied coating system
- Application procedure
- Service environment
- Physical and instrumental characterization of the failed coating
Assessment of the fundamental causes behind coating failures is critical for understanding the underlying causes, so as to formulate appropriate corrective and preventative strategies for dealing with coating failures.
Coating failures may appear during application, at the stage of curing or after a certain period of service life. Statistics show that as much as 95% of all coating failures are a result of poor surface preparation and application. Often failure takes place for a combination of reasons that require an expert eye.