How Does Laser Cleaning Work 3 Types Of Laser Cleaning Methods

　　We all know that laser cleaning technology is a new cleaning technology that utilizes the interaction between laser and matter. It has the advantages of simple operation, high precision, low damage, low emission and environmental protection. Researchers have been widely concerned and research and made a lot of important research results, so laser cleaning is very promising. But how does laser cleaning work? This article will answer this question for you.By comparison, it can be seen that laser marking machine It has certain advantages and great cost performance. https://riselaser.net/products/laser-marking-machine

　　3 Types of Laser Cleaning Methods

　　Laser cleaning is a complex process. It involves multiple fields of knowledge such as Physics, Chemistry, Mechanics, Thermodynamics, and multiple time scales such as nanoseconds, milliseconds, and microseconds. Its common cleaning mechanisms are: decomposition, melting, ablation, vaporization, vibration, splashing, stripping, expansion and explosion. Cleaning process generally exists in a variety of cleaning mechanism synergize with each other to achieve the cleaning requirements. Comprehensive analysis of different cleaning methods, laser cleaning is mainly divided into three types: dry cleaning, wet cleaning, plasma cleaning.

　　1.Dry Cleaning

　　Dry cleaning is the direct exposure of a laser beam to a contaminated surface of a substrate. Using the high energy properties of the laser to achieve efficient removal of contaminants, the cleaning environment is natural air or an inert protective gas. The substrate and surface dirt due to the absorption of part of the laser energy and temperature rise. Generally, the high energy in the center of the laser action leads to high temperatures. The contaminants are removed by vaporization, ablation, photochemistry, and thermal decomposition. Away from the center of the laser energy and temperature is low, contaminants removed by thermal stress, thermal shock and physical fracture. Therefore, dry laser cleaning is suitable for most operating environments and contaminants.

　　2.Wet Cleaning

　　Wet laser cleaning is realized with the aid of a liquid film. A liquid film is preset on the surface of the workpiece for cleaning, and the laser is directly irradiated. The liquid instantly heats up dramatically, generating a strong impact force that removes contaminants from the surface of the substrate. According to the distribution of laser energy between the substrate and the liquid film, the wet cleaning method can be divided into three forms.

　　Strong substrate absorption, substrate and liquid film co-absorption, and strong liquid film absorption. Among them, the strong substrate absorption has the best cleaning effect, which is mainly closely related to the wavelength of the laser. Wet laser cleaning needs to prepare the liquid membrane in advance. And the operation process of preparing liquid film is tedious, and it is not applicable to the cleaning of large parts. However, it is suitable for the removal of particle contaminants on the surface of electronic components or other precision parts. Therefore, the development and application of wet laser cleaning is subject to certain restrictions.

　　3.Plasma Cleaning

　　Unlike the previous two cleaning methods, the plasma cleaning process does not involve contact between the laser and the substrate surface. The laser is launched in a direction parallel to the surface of the substrate and focused by a converging lens. The high energy generated causes the gas to be penetrated and forms a laser plasma. The plasma contacts the particles in the process of rapid expansion, and the removal is achieved by the mechanical action of the shock wave.

　　Plasma cleaning has no limitation on the laser wavelength, but there are still several shortcomings in the cleaning process due to plasma generation. First, only occurs at the focal point, the cleaning range is small. Second, the dirt to be cleaned and the distance between the plasma control requirements are higher, the operation is more difficult. Third, it is only applicable to the removal of particles or adhesion of small pollutants.