Laser paint stripping process Emissions: Q-switched vs. pulsed Nd:YAG laser

Laser removal of surface coatings is being considered as an “environmentally friendly” replacement for traditional solvent coating removal processes during the repair and refurbishment of composite helicopter main rotor blades. The process emissions produced during removal of an epoxy paint from this thin composite substrate using both a Q-switched Nd:YAG laser and a pulsed Nd:YAG laser were collected, analyzed, and compared. Particulate matter was collected and analyzed for concentration of various elemental metals. Vapor emissions were collected and analyzed for volatile organic compounds, CO, NO2, and nitrous compounds. The processed substrate and particulate emissions were evaluated under a microscope. The results provide insight into the different removal mechanisms exhibited by these two lasers, and demonstrate that choice of laser plays a role in the resultant process emissions.