Powder coating defects and solutions ـ poor mechanical-chemical properties
After powder application certain defects might appear on the coated part which we have elaborated along with the factors that could be responsible for causing these.
Poor mechanical-chemical properties of powder coating
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Poor chemical and mechanical properties
Discrepancy in the chemical and mechanical properties of the applied coating with the specifications of the Technical Data Sheet (TDS)
- Under-cured film
- Presence of grease and oil on the substrate
- Thick phosphate layer
- Problem in the formulation of powder coating
- Using clear top coat causes the chalking effect in the coating
- Thick coating film
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Poor adherence
the coating film hardly adheres to the substrate
- Under-cured film
- Improper pretreatment of part
- A change in the quality of part
- Thick phosphate layer
- Poor adherence of second layer
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Poor chemical resistance
Coating has low resistance towards chemicals
- Under-cured film
- Using unsuitable powder coating
- Presence of holes and craters in the coating
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Poor corrosion resistance
Poor resistance of coating against corrosion
- Under-cured film
- Improper pretreatment of substrate
- Presence of holes and craters on the coating
- Poor coating on the corners and edges of part
- Choosing unsuitable resin base
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Chipping and peeling off of film
Cured film easily flakes and peels off the part
- Under-cured film
- Improper pretreatment of part
- Presence of rust on substrate
- White rust
- Film does not adhere to edges and corners that have been cut by laser
- Presence of dirt or contaminants on the surface
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Scratch marks on the film
Poor resistance to scratches and abrasion
- Under-cured film
- Packing causes abrasion on the coated surface
- Easily scratched powder coating
- Abrasion during assembly
- Coated part is transported in a non-standard container
Prepared by: Mojtaba Zeinal