Effect of Thermal Stress on Paint Peeling Caused by Atmospheric Plasma Irradiation

Paint protects the outer surface of ships. The antifouling component of paint prevents aquatic organisms from attaching to the surface of the ship. However, marine paints deteriorate with time. Therefore, periodic repainting is required. Repainting is performed via sandblasting, in which an abrasive is sprayed onto the surface of the paint. However, in this method, the base material of the paint is damaged. According to previous studies, when a painted surface is irradiated by plasma, the paint tends to peel off easily. Herein, we hypothesize that the paint is easily peeled off because of the thermal stress induced by the plasma during irradiation. To verify this hypothesis, we experimentally investigated the effect of thermal stress due to atmospheric pressure plasma. Results show that the streamer is a factor that easily peels off the paint. In addition, the effect of thermal stress due to the crosslinking reaction was confirmed via plasma irradiation. Furthermore, the effect of chipping due to intermittent discharge was explored by observing the painted surface via SEM.