In recent years, with the enhancement of people’s awareness of environmental protection, it has brought tremendous challenges to the development of the cleaning industry worldwide. Various cleaning technologies that benefit the environment have emerged. Laser cleaning technology is one of them. The so-called laser cleaning technology refers to the use of high-energy laser beam irradiation on the surface of the workpiece, so that the surface of the dirt, rust or coating instantaneous evaporation or peeling, high-speed and effective removal of the cleaning object surface attachments or surface coating, so as to achieve a clean process . It is a new technology based on the interaction effect of laser and material. Unlike traditional mechanical cleaning methods, chemical cleaning methods and ultrasonic cleaning methods (wet cleaning processes), it does not require any CFC-based organic solvent that destroys the ozone layer and has no pollution. , No noise, harmless to the human body and the environment, is a "green" cleaning technology.
Compared with traditional cleaning methods such as laser cleaning and mechanical friction cleaning, chemical corrosion cleaning, liquid solid strong impact cleaning, and high frequency ultrasonic cleaning, there are obvious advantages. It is efficient, fast, low cost, small heat load and mechanical load on the substrate, cleaning is non-injury; waste can be recycled, no environmental pollution; safe and reliable, does not harm the health of operators; can remove all kinds of different thickness, different The coating of the ingredients; easy to achieve automatic control of the cleaning process, remote cleaning and other remote control.
The principle and method of laser cleaning
Lasers are characterized by high directivity, mono chromaticity, high coherence and high brightness. By focusing the lens and Q-switching, the energy can be concentrated in a small space and time range. In the laser cleaning process, the following characteristics of the laser are mainly used:
1. Lasers can achieve high concentration of energy in time and space. Focused laser beams can generate high temperatures of several thousand degrees or even tens of thousands of degrees in the vicinity of the focal point, allowing the dirt to instantly evaporate, gasify, or decompose.
2. The divergence angle of the laser beam is small and the directionality is good. The laser beam can be condensed into light spots of different diameters by the concentrating system. Laser beam spots of different diameters are controlled under the same laser energy.
3. The energy density of the laser can be adjusted so that the dirt expands. When the expansion of the dirt is greater than the adsorption of the dirt on the substrate, the dirt will be off the surface of the object.
Laser cleaning application
2. metal surface paint layer and welding point removal;
3. remove oxides, oil, grease and product residues;
4. Historical restoration and preservation.