Temperature Limits for E-Coated Parts
Q. What are the temperature limitations for electrocoated parts and products? K.L.
A. Electrocoat is a technology that uses organic resins, and organic and inorganic pigments during formulation of the coatings. The organic components used have temperature limitations specific to their chemical composition or chemical family (i.e., epoxy, acrylic, etc.). To properly determine the temperature limitations of your electrocoated products, we first need to define the duration of exposure. Typical electrocoats can support continuous high temperature exposures in the range of 430–450°F without any significant film degradation, and without any negative effects on film resistance or performance. At higher temperatures, the electrocoat film gets harder as the unreacted polymer from the previous electrocoat cure completes its crosslinking and cure.
As the temperature increases to 475–525°F, the organic resins and components start smoking heavily and the remaining film loses chemical resistance.
As temperature increases above 550°F, the film starts burning slowly, loses thickness rapidly, and loses all physical and corrosion properties.
Above 750°F, the electrocoat film will burn to the point of disappearance.
Although there have been some attempts to formulate electrocoats with additives to increase temperature resistance in an effort to eliminate heat shielding parts exposed to high temperatures from automotive exhaust pipes and systems, this has not been approved for operational use.
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