Comparison and Improvement of Millisecond Pulsed Laser and Nanosecond Pulsed Laser for Cleaning to Remove Paint Coating from Aluminum Alloy Surface

• Published in: Journal of materials engineering and performance Vol. 33; no. 12; pp. 5765 - 5775
• Main Authors: Bi, Siyuan, Lei, Zhenglong, Feng, Junhua
• Format: Journal Article
• Language: English
• Published: New York Springer US 01.06.2024
• Subjects: Characterization and Evaluation of Materials; Chemistry and Materials Science; Corrosion and Coatings; Engineering Design; Materials Science; Quality Control; Reliability; Safety and Risk; Technical Article; Tribology; pulse width; dynamic behavior; laser cleaning; paint coating; surface topography
• ISSN: 1059-9495; 1544-1024
• DOI: 10.1007/s11665-023-08344-z

Experiments on the cleaning of primer coatings and composite coatings were carried out by millisecond pulsed CO 2 laser and nanosecond pulsed fiber laser, the dynamic behavior during the cleaning process was observed by high-speed camera and infrared thermal imager, and the micro- and macro-morphologies of the surface of the samples after cleaning were analyzed. After using millisecond pulsed CO 2 laser to clean the paint coating, there are residual combustion products, and it is easy to thermally deform the substrate. When using nanosecond pulsed fiber laser to clean the primer coating, the laser energy can be precisely controlled to avoid damage to the substrate, but it is difficult to remove composite coatings in a single scan. Using 300 W nanosecond pulsed laser for multiple scans can remove thicker paint coatings with less damage to the substrate, but the cleaning efficiency is greatly reduced. For this, a new method of multi-laser combined cleaning is proposed. The composite coatings are thinned with a 200 W millisecond pulsed laser, and then the final cleaning is done by a 200 W nanosecond pulsed laser, and a clean substrate surface without visible damage is obtained. After cleaning, the coating residue rate is 0.965%, the surface roughness is 3.19  μ m, and the surface contact angle is 33.3°, which is conducive to the reattachment of the subsequently applied coatings.