Laser surface cleaning and real-time monitoring

Abstract

Laser cleaning has emerged as an effective cleaning technique for removing contaminants from solid surfaces. Dry laser cleaning and steam laser cleaning have been developed recently, relying on pulsed laser heating of the surface without and with the presence of a thin liquid coating. Two cleaning models from the viewpoint of force and energy for dry laser cleaning and a cleaning model for steam laser cleaning were established for removal of particles from solid surfaces by taking Van der Waals force, capillary force and cleaning force into account. The models not only explain the influence of laser fluence on cleaning efficiency, but also predict the cleaning thresholds. Laser-induced removal of film-type contaminants has been studied and the surface cleanliness can be monitored in real time by acoustic and electric means.