Laser cleaning system is mainly used in the surface treatment of aircraft body in the aerospace industry. When repairing and maintaining an aircraft, it is basically necessary to remove the old paint on the surface in order to spray new oil sandblasting or steel brush sanding and other traditional methods of cleaning the surface paint film.
Laser cleaning systems have long been used in the aviation industry in Europe. The surface of the aircraft needs to be repainted after a certain period of time, but the original old paint needs to be completely removed before painting. The traditional mechanical paint removal method is easy to cause damage to the metal surface of the aircraft, which brings hidden dangers to safe flight. Using multiple laser cleaning systems, the paint can be completely removed from an A320 Airbus within two days without damaging the metal surface.
The principle of laser cleaning on aircraft surface cleaning:
The process of pulsed laser cleaning relies on the characteristics of the light pulses generated by the laser, based on photophysical reactions caused by the interaction between the high-intensity beam, the short-pulse laser, and the contamination layer. Its physical principles can be summarized as follows:
1. The beam emitted by the laser is absorbed by the contamination layer on the surface to be treated.
2. The absorption of large energy forms a rapidly expanding plasma (highly ionized unstable gas), which produces a shock wave.
3. The shock wave breaks the contaminants into fragments and is rejected.
4. The light pulse width must be short enough to avoid heat build-up that would damage the surface being treated.
5. Experiments show that when there is oxide on the metal surface, plasma is generated on the metal surface. Wuhan Ruifeng Optoelectronics Laser is one of the first batch of laser equipment companies. With more than ten years of R&D and production experience, it leads the industry in terms of technology and integration. Since its establishment, the company has always paid attention to the research and development of laser technology and the development needs of customers, and is committed to providing perfect material processing solutions for each enterprise.
Plasma 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 appearance of plasma. If the energy density exceeds this threshold, the substrate material will be destroyed. In order to carry out effective cleaning on 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 the contamination layer. If the contamination layer is thick, multiple pulses are required for cleaning. The number of pulses required to clean the surface depends on the degree of surface contamination. An important consequence of the two thresholds is the self-control of cleaning. Light pulses with an energy density above the first threshold will reject contaminants until they reach the substrate material. However, since its energy density is below the destruction threshold of the substrate material, the substrate is not damaged.
In addition to the application in the aerospace industry, the laser cleaning machine has the characteristics of long service life, environmental protection, low energy consumption, high efficiency, and simple and convenient maintenance. It has been widely used in various industrial fields, such as peeling paint and coating oxides. Removal, mold cleaning, restoration of ancient cultural relics, pretreatment of parts joining, etc.