The so-called laser cleaning technology refers to the use of high-energy laser beams to irradiate the surface of the workpiece to instantly evaporate or peel off the dirt, rust spots or coatings on the surface, and effectively remove the surface attachments or surface coatings of the cleaning object at high speed, so as to achieve a clean process. . Laser cleaning machine is a new and efficient environmental cleaning technology, which is a new technology based on the interaction effect between laser and matter. Different from the traditional mechanical cleaning method, chemical cleaning method and ultrasonic cleaning method (wet cleaning process), it does not require any CFC organic solvent that destroys the ozone layer, no pollution, no noise, harmless to the human body and the environment, is a kind of ” Green” cleaning technology. Nowadays, traditional cleaning processes are gradually replaced in many fields.
Laser surface cleaning is based on a photophysical reaction caused by the interaction between a high-intensity beam, a short-pulse laser, and the contamination layer. Its physical principles can be summarized as:
1. The beam emitted by the laser is absorbed by the contamination layer on the surface to be treated, and the absorption of large energy forms a rapidly expanding plasma (highly ionized unstable gas), which generates a shock wave, and the shock wave makes the contaminant into fragments and removed;
2. The optical pulse width must be short enough to avoid heat build-up that would destroy the surface being treated;
3. Experiments show that when there is oxide on the metal surface, the plasma is generated on the metal surface.