Powder Flowability - Solving a Sticky Problem in France
Finishing and powder coating is a critical process in automotive manufacturing and one where cost optimization and innovation are key. To achieve a high-quality finish from a powder coating, complete and accurate information about powder flowability is essential. A powder coating must be free flowing and it must fluidize well in the fluidization bed. This ensures that individual particles are separated, improving the electrostatic charge that can be applied to the powder so that it flows more easily through the spray gun to give an even finish. The flowability of a powder is also important in powder recovery - a free-flowing powder will not clump during recovery, reducing the amount of waste.
Automotive powder coatings are a mixture of several components, such as resin, crosslinker, pigments, flow aids and degassing solvent. Their flowability is affected by many factors, most being especially sensitive to moisture absorption and exposure to heat, for example. The way they are stored can also have a large impact on their subsequent performance in the spray-painting booth.