Sometimes powder coating will chip or crack, and continue peeling just like an egg shell. Not only does chipped powder coating look bad, it can it allows the elements to wear away the precious parts you tried so hard to protect. If powder coating is so strong and durable, what causes it to crack or chip?
If a surface is not properly pre-treated before it is powder coated, sediment or corrosion can cause the powder coating to crack or chip. In order to properly pre-treat an area, you have to clean the material, strip away any corrosion, degrease (if applicable) the surface, and create a surface that the powder coating can attach to. There are two main types of pre-treatments, abrasion and chemical coatings. Both are tricky processes and must be done properly to extend the life of your powder coating.
Edges or Corners are not Coated Properly
The most common reason why your powder coating may chip or crack is because the edges or corners were not coated properly. Corners and edges are hard to reach and coat, and sharp metal edges may poke through the powder coating. If any piece is not powder coated, no matter how small, wind, water, and friction can cause the powder coating to begin to chip away.
Powder coating must be cured at a certain temperature for the right amount of time, otherwise the powder coating will not be as durable. You can both under-cure and over-cure powder coating. Over-cured powder coatings will typically show signs of discoloration, while under-cured powder coatings will allow the material to become chipped and eroded.
Applied Too Thick or Too Thin
If the powder coating is applied with too much or too little powder coating, many problems can occur. If too little powder is applied, the surface will be patchy, unprotected, and will corrode more easily. It also may be too shiny. If too much powder is applied, it can result in poor adhesion, and it will probably crack, peel, or bubble. Over or under coating also leads to imperfections in the finish.
Even if the material is properly powder coated, it is possible that it just wears away from the pressures of the environment. If you use your powder coated object in extreme heat, cold, or around rough substances such as dirt and salt, it may corrode faster than you intended. The environment will slowly wear down on the powder coating, and it will eventually be less effective in protecting your gear.