The Problem-Solution Series: Part 9

Problems with Cured Coating Cohesion

Problem:
Have you been noticing less than desirable cohesion when curing powder-coated parts? Little or no cohesion on a cured part can stem from multiple origins. We're here to help you fix this mishap and maintain optimal curing results.

Origin:
The phosphate coating weight is too low, usually due to the wrong temperature or amount of time.

Solution:
In order to increase the weight of the coating, increase the phosphate or accelerator concentration. If this fails to work, increase both of these concentrations. Additionally, increase the process, time, and temperature.

Second Origin:
Adversely, the phosphate coating weight could be too high.

Solution:
Reduce the concentrations, time, or temperature of the process.

Third Origin:
Potentially, leftover surfactants and soils remain, limiting phosphate disposition.
 

Solution:
Adjust the cleaning and rinse stages. Be sure to orient the parts for maximum coverage, and clean and adjust the spray nozzles for this same result. Throughout the process, always be sure to maintain high rinse tank water purity.
 

Fourth Origin:
There are unidentified soils remaining in the metal and/or somewhere within the process.
 

Solution:Verify that all of the metal and process soils have been identified. To eradicate unwanted metal or soils, treat surfaces chemically or mechanically through blasting or polishing.

For additional information on powder coatings, visit our website at tcipowder.com. Feel free to Contact us today to have someone from our experienced team answer your powder coating questions or to see how we can help you with your powder coating needs.