Pulsed Nd:YAG laser cleaning process depends on the characteristics of the light pulse generated by the laser, based on the interaction between the high intensity beam, the short pulse laser and the contamination layer
Photophysical reaction. Its physical principles can be summarized as follows
A The laser beam is absorbed by the contaminated layer on the surface to be treated
B The absorption of large amounts of energy forms a rapidly expanding plasma (a highly ionized, unstable gas) that generates a shock wave
C shock waves break contaminants into fragments and remove them.
D light pulse width must be short enough to avoid heat accumulation that damages the treated surface.
E Experiments show that plasma is generated on the metal surface when there is oxide on the metal surface.
Plasma is only produced if the energy density is above a threshold, which depends on the contaminant or oxide layer being removed. This threshold effect is effective in ensuring the safety of the base material
Effective cleaning is very important. There is a second threshold for plasma. If the energy density exceeds this threshold, the substrate material will be destroyed. In order to ensure the safety of the base material
To carry out effective cleaning, 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 thick, multiple pulses are required to clean it. The number of pulses required to clean the surface depends on the surface contamination
An important result produced by the two setting values is the white control of cleaning. The light pulse with high energy density at the first setting value will remove contaminants easily until the base material is reached, however
Because its energy density is lower than the damage domain of the base material, the base will not be damaged.
Advantages of laser cleaning machine 100w:
Compared with mechanical friction cleaning, chemical corrosion cleaning, liquid solid strong impact cleaning, high-frequency ultrasonic cleaning and other traditional cleaning methods, laser cleaning has obvious advantages
1. Laser cleaning is a "green" cleaning method, without the use of any chemical agents and cleaning liquid, cleaning down the waste is basically solid powder, small volume, easy to store recyclable can easily solve the environmental pollution caused by chemical cleaning
2. The traditional cleaning method is often contact cleaning. There is mechanical force on the surface of the cleaning object, the surface of the damaged object or the cleaning medium attached to the surface of the cleaning object, can not be removed
These problems are easily solved by non-abrasive and non-contact laser cleaning which produces secondary pollution
3. Laser can be transmitted through optical fiber with robot hand and robot, convenient to achieve long-distance operation, can clean the traditional method is not easy to reach parts, which can be used in some dangerous places to ensure the safety of personnel
4. Laser cleaning can remove various types of pollutants on the surface of various materials, to achieve the cleanliness that can't be achieved by conventional cleaning. The eye can also have a choice without damaging the surface of the material
Clean the surface of the material for contaminants
5. Laser cleaning efficiency is high, save time
6. The purchase of laser cleaning system although the one-time investment is high in the early stage, the cleaning system can be used steadily for a long time with low operation cost and no consumables. Take our company's laser cleaning machine as an example, every hour
The line cost is only about 1 yuan, and more importantly, it can be easily automated
Application of laser cleaning:
Laser cleaning can not only be used to clean organic pollutants, but also can be used to clean inorganic materials, including metal corrosion, metal particles, dust and so on. Here are some practical applications in steam
Car manufacturing, semiconductor wafer cleaning, precision parts processing and manufacturing, military equipment cleaning, building cleaning, cultural relics protection, circuit board cleaning, precision parts processing and manufacturing, liquid crystal
Monitor cleaning, sunsweet residue removal and other fields can play an important role.