At EWI, I was fortunate to be able to use an IPG q-switched fiber laser for several months. During this time I evaluated it for removing paint from aircraft aluminum along with other applications.
Q-switched lasers are unique in that they deliver very high power bursts of laser energy in short pulses. The term “q-switch” comes from the fact that the laser beam “quits” momentarily while the power builds and is then released. With the combination of high power and short pulse length, q-switched lasers and other similar short pulse length lasers are used to do more than just melt metal. They can vaporize and ablate materials with less wasted heating.
The exact model was an YLP-HP-50-100-10-500. This laser had 500-watts average power, a pulse length range of 25 to 200-ns in select increments, and a 600-micron delivery fiber. The pulse frequency range for this laser was 9.9 to 50.1-kHtz. The focused spot size was about 600-micron.
The collimated beam from the IPG q-switched fiber laser was delivered to a scanner where mirrors scanned the focused q-switched laser beam in a pattern of stripes over aircraft aluminum with multiple layers of paint. The pulse frequency was 24-kHtz. By varying the laser scanner speed, the overlap between stripes, the laser power, and the number of passes, different paint removing results were obtained. The picture above shows a frame from the video. Two passes are made at 100% power and 4 passes at 25% power. These settings were able to remove much of the paint down to base metal. Q-switched lasers can be also be used for cleaning and surface texturing.
Video of Q-Switched Fiber Laser Paint Removal
For more information on Q-switched fiber laser processing please contact Jay Eastman at jeastman@ewi.org.
EWI also has extensive experience with laser paint stripping using continuous wave fiber lasers and CO2 lasers using EWI patented polygon scanner. For more information about laser paint stripping, contact EWI Technology Leader Stan Ream at sream@ewi.org.