CED Coating Defect that Affect Your CarsAdmin
Cathode Electro Deposition or CED is a modern and environment-friendly water based coating for metal substrates. The coating is a combination of dip and spray that is performed on the metal components. During the coating, there can be various defects associated with electrocoat tank and possible causes.
Common CED Coating Defect is Mentioned Below
Dirt: Dirt comes from three different sources. Process dirt develops within the bath or rinses from pump shear and improper filtration. Initially, dirt appears on a horizontal surface but it affects all surfaces. Secondly, environmental dirt is produced by airborne particles. Due to this, ventilation fans and electrocoat areas exposed to vehicular traffic are at risk. Thirdly, oven dirt is a result of condensation of electrocoat by-products. When compared with others, oven dirt is more surface-oriented, whereas environmental and process dirt is fixed in the paint film to some extent.
Thin coating: Such coats can be caused due to a low voltage, poor contact, inadequate electrode surface, high part loading, and insufficient deposition time. Proper electrical supply, clean hooks, and retaining the proper coating surface to electrode ratio is important for building film properly. This can also be improved by increasing voltage, deposition time, and bath temperature.
Throwing power: Poor throwing power is usually related to low voltage, low bath solids, high solvent levels, low conductivity, and insufficient deposition time. It can be improved by increasing all the variables and decreasing bath temperature and solvent. Throwing power also can be affected by adding the auxiliary electrodes that are close to the areas where more film building is required.
Color variations: This can be caused due to various factors such as iron contamination, poor tank agitation, and improper cure. Iron contamination may result due to the browning of the coated film. Oven problems can fade away cured films.
All these CED coating defect can be easily removed. Pre-treatment, CED, ultra filtration and curing are some of the steps required in CED coating. For coating the parts of cars, it is necessary to follow the process step by step. With this coating, car parts can be provided high durability. Therefore, the coating must be done carefully to cover all the parts of car.