After the optical lens is finely ground by the abrasive liquid, there is still a crack layer about 2–3m thick on the surface. The method to eliminate this crack layer is polishing. The mechanism of polishing and grinding is the same, except that the tool material used is different from the slurry. The materials used for polishing include cloth, polyurethane and pitch, which usually require high precision. For the polished surface, the most commonly used material is high-grade polished asphalt.
Using asphalt to polish, the fine surface of asphalt drives the polishing liquid to grind the surface of the lens to generate heat, which makes the glass melt and flow, melt away rough vertices and fill up cracks At the bottom of the valley, the crack layer is gradually removed.
Currently, the polishing powder used for polishing glass lenses is mainly cerium oxide (CeO2). The proportion of the polishing liquid varies according to the polishing period of the lens. Generally, the initial stage of polishing When designing the optical mold with the polishing lens, use a polishing liquid with a higher concentration. After the surface of the lens is bright, use a polishing liquid with a dilute concentration to avoid orange peel on the mirror surface (fogging of the lens surface).
The movement mechanism used for polishing and grinding is the same. In addition to the different polishing tools and working fluids, the environmental conditions required for polishing are also stricter than those used for grinding. The general things to pay attention to when polishing are as follows: There should be no impurities in the surface of the polishing asphalt and the polishing liquid, otherwise it will cause scratches on the mirror. The polished asphalt surface must be consistent with the lens surface, otherwise it will be bounced during polishing, which will bite the polishing powder and scratch the lens surface.
Before polishing, it must be determined whether there are scratches or punctures on the surface of the lens after polishing. Whether the size and material of the polishing tool are appropriate. Whether the hardness and thickness of the asphalt are appropriate. During the polishing process, attention must be paid to the condition and accuracy of the lens surface at all times. In the inspection of lens surface defects, because the process of detecting laser lenses is judged by personal vision and methods, the inspector should have a deep understanding of the specifications of scratches and sand holes, and often compare the standard samples for scratches and sand holes. Version to ensure the correctness of the inspection.
The application range of laser cutting is very wide. Most organic and inorganic materials can be laser cut. The laser cutting ability is not affected by the hardness of the material being cut. Any hardness material can be cut, such as brittle, extremely soft, and extremely hard materials. Almost all metal materials can be cut by laser, and the thickness that can be cut ranges from a few micrometers of foil to 50mm of plates. It can also be used to cut non-metallic materials such as plastics, natural materials, cloth, stone tombs and ceramic lamps. For example, the wood processing industry has used laser to cut plywood and particleboard, and the clothing industry is used to cut a large number of clothing materials.
The laser beam is highly controllable. Modern laser cutting systems can easily cut parts and patterns of various shapes. It can cut flat high-power laser mirror workpieces and Cutting three-dimensional workpieces. Laser cutting can start at any point (perforate first), and the incision can be carried out in any direction without being restricted by the cutting workpiece. The laser beam has unlimited profiling cutting capabilities. The laser beam is easy to combine with the numerical control system and the computer control system to realize the automation of the cutting process. The laser cutting machine can also be operated in multiple positions, and one machine has multiple functions.
Don’t think that the air blowing system on a laser cutting machine does not seem to have any practical effect. The average person treats it as a 'suction' or ordinary air blowing system during processing. Used to fix the material or blow away the cutting residue on the cutting platform to see. In fact, the usefulness of the auxiliary gas is of great importance to the laser cutting machine. On the processing table of the non-metal laser cutting machine, the auxiliary gas is mostly called 'suctionIt also has the effect of fixing the material, but its main mirror function is to 'suck away' the excess dust and slag generated in the cutting gap during the processing of the laser cutting machine, so that the laser cutting machine processes the incision It is neat and smooth without burrs and slag adhesion, and most non-metallic materials have a low melting point. The existence of an auxiliary gas blowing system can avoid unnecessary radiation of heat during laser cutting machine processing, and make the cutting edge extremely fine And precise.
On a metal laser cutting machine, there are usually auxiliary gases ejected coaxially from the nozzle of the laser head. These auxiliary gases can escape the slag on the one hand to ensure the cutting quality, like oxygen Or other active gases can also help melt cutting. For example, when oxygen is used to cut stainless steel, it is ejected coaxially with the laser from the nozzle of the laser cutting machine, which can release a large amount of oxidation heat, thereby speeding up the cutting speed.
So the auxiliary gas blowing system is an integral part of the laser cutting machine processing process.