INTRODUCTION OF COMPUTER SIMULATION TECHNOLOGY FOR ELECTRODEPOSITION PAINTING PROCESS 2011-32-0639

The electrodeposition painting can make a coat adhere not only to the exterior surface but also on the inside of an object, and has excellent corrosion resistance. Therefore, it is widely used as paint for anti-corrosion to various vehicles.

In electrodeposition painting, by the electricity from an electrode flowing into the surface of an object through paint solution, a paint deposits to the surface of an object and a paint film is formed. Therefore, if the object is simply in contact with paint solution, a paint film will not necessarily be formed. For example, even if paint solution has touched, since the electrical resistance of paint solution is not high, sufficient current flows through the outside of a motorcycle frame, nor the inner surface of the automobile body and a paint film may not be formed. In order to check the paint film thickness of electrodeposition painting conventionally, it was measuring by disassembling the actually painted object. As a result of measurement, when paint film thickness is inadequate, it is necessary to cope with the addition of a hole, part form change, etc. However, when changing structure for a measure, investment of large sums, such as change of a press die, is needed. Furthermore, since it will be necessary to verify influence on other performances again, a huge man hour and a development period are needed.

In order to solve these problems, the deposit behavior of an electrodeposition painting and the body of a car or a motorcycle with complicated form were modeled faithfully, and the computer simulation technology which can predict electrodeposition paint film thickness by taking into consideration movement of the body within an electrodeposition painting tank was developed further. We compared the results of analysis using this technology with the actual paint film thickness, and confirmed that the predicted thickness and the actual thickness are almost exactly the same, and hence the prediction accuracy of the analysis is sufficiently high. By applying this simulation technology to vehicles development or a facility design, improvement in paint quality, shortening of a development period, reduction of change-of-design expense, etc. are expectable.