Degumming Failure Analysis of 3M Tape Used in Door Dealing

Door sealing degumming not only affects the productivity of car plants but also causes customer complaint for water leakage. In order to investigate the degumming reason, the adhesive performance of the tape, the reaction time between the tape and paint surface, the surface energy and cleaning of the paint, the gap between the door inner sheet and the body outer sheet, and the door sealing assembly process were studied in detail. The results show that the degumming is mainly related to the surface cleaning and pressure. The 3M tape has excellent adhesive performance with the door paint under the following conditions: 80% of the tape is under the pressure higher than 20 N and the rest is not lower than 10 N, the paint is clear and has a minimum surface energy of 40 mN/m with a minimum polar fraction of 4 mN/m, the reaction time between the tape and paint surface is longer than 40 min, and there is no obvious shear force during this period.