E-coating or electrophoretic painting is a coating process used for depositing an organic paint film by means of electrical charge. Although this process is used in different applications, it is mostly known for its application in the automotive industry as a primer coat for the vehicle structure or Body-in-White (BIW). The function of this coating is mainly corrosion protection and therefore it is important to have a 100% coverage, including all inner reinforcement structures and cavities.
Paint deposition on inner structures and inside cavities depends on the access of current paths and therefore a proper design of the location and size of perforations in the different sheet metal components is critical. Validating the impact of (changes on) this design on the e-coat process, inside inner structures and cavities by means of prototype BIW's that pass through the e-coat line, is a very expensive and time consuming effort. In reality, only a limited number of trials are possible before the design of the car is frozen and taken into production. Moreover, the cost of design changes increases along the development stages of the vehicle program, so an early definition of e-coating perforations is paramount.
The Elsyca ECoatMaster software platform is used both in-house on a project base and on-site at key customers for executing e-coat simulations. Elsyca ECoatMaster employs FEA technology for predicting the paint thickness at each location on a fully detailed vehicle, taking into consideration the e-coat line infrastructure and all relevant process conditions, such as voltage program, flow conditions and electrochemical paint characteristics. The accuracy that can be obtained from these simulations is very high, with typical differences between simulated and measured paint layer thickness values below 2 micron.
An example of the paint build-up on a BIW as it travels through the e-coat line can be viewed here.