The cleaning process of laser cleaning equipment depends on the light pulses generated by the laser, based on the photophysical reaction caused by the interaction between high-intensity beams, short-pulse lasers and contamination layers.
Laser cleaning equipment plays an important role in many industries, such as automobile manufacturing, semiconductor wafer cleaning, precision parts processing and manufacturing, building exterior wall cleaning, cultural relic protection, circuit board cleaning, precision parts processing and manufacturing, liquid crystal display cleaning, Gum removal, grease removal, paint removal and more.
How does laser cleaning equipment remove paint?
To understand how laser cleaning removes paint, you must first understand the cleaning mechanism of laser cleaning equipment.
The paint applied to the metal surface is equivalent to a layer of special plasma, which protects the metal from corrosion and oxidation. Plasma, on the other hand, is only generated when the energy density is above a threshold, which depends on the contamination or oxide layer being removed.
This threshold effect is important for effective cleaning while keeping the substrate material safe. There is also a second threshold for the emergence of plasma. If the energy density exceeds this threshold, the substrate material will be destroyed. In order to carry out effective cleaning under the premise of ensuring the safety of the substrate material, the laser parameters must be adjusted according to the situation, so that the energy density of the light pulse is strictly between the two thresholds.
Each laser pulse removes a certain thickness of contamination layer. If the contamination layer is thicker, multiple pulses are required for cleaning. The number of pulses required to clean a surface depends on the degree of contamination of the surface. An important consequence of the two thresholds is the self-control of the cleaning.
Light pulses with an fluence above the first threshold will reject the contaminants until they reach the substrate material. However, since its energy density is below the damage threshold of the substrate material, the substrate will not be damaged.
Based on the above, when using laser cleaning equipment to clean the paint on the metal surface, the threshold value must be well controlled. When the threshold value is appropriate, laser cleaning can be performed. When the threshold value cannot be set, it means that the laser cleaning equipment cannot meet the cleaning requirements. One of the reasons why cleaning equipment is not omnipotent. However, with the continuous deepening of laser research and development, the functions of laser cleaning equipment will become more and more powerful, and it may reach the point where everything can be washed.
