preface

Carbon dioxide laser is a kind of laser with high continuous output power at present. It developed earlier and its commercial products are more mature. It is widely used in material processing, medical use, military weapons, environmental measurement and other fields. In terms of the development and application of lasers, CO2 lasers were made and applied earlier and more frequently. As early as the late 1970s, CO2 lasers were imported directly from abroad for industrial processing and medical applications. Since the late 1980s, CO2 laser has been widely introduced and used in the field of material processing.

In recent years, although CO2 laser processing equipment is becoming more and more popular, laser is a new tool after all, and laser processing technology is also different from traditional processing methods. Therefore, in the process of introducing and using CO2 laser, industry has encountered a variety of problems, causing a lot of trouble to many manufacturers. This paper analyzes the application status and evolution of CO2 laser in different fields, and puts forward some common problems in the process of using CO2 laser. According to the classification of CO2 laser power, this paper expounds the application status and evolution of CO2 laser in various industries, lists and analyzes the main problems that CO2 laser users will face, and finally discusses the future of CO2 laser application The prospect is put forward.

2. Application and development of industrial CO2 laser

In order to introduce the application of CO2 laser processing in detail, according to its cost, this paper takes the laser output power range (less than 200 watts, between 200 and 1600 watts and more than 1600 watts) as the division standard, and introduces its application in various fields one by one.

2.1 application of low power (less than 200W) CO2 laser

The early imported and manufactured CO2 laser machines were all low-power lasers with power less than 200 watts. It is mainly used in electronic industry (such as resistance manufacturing, IC logo), non-metal processing industry (bamboo and wood carving, clothing, shoe making, jewelry manufacturing, etc.) and some medical and research units.

CO2 laser beam is focused on IC or semiconductor module through a light mask for marking. This kind of CO2 laser is mainly tea pulse type. However, with the rapid development of logo processing speed and quality, as well as the rapid development of solid-state laser, the newly introduced logo processing laser has been gradually replaced by solid-state YAG laser.

The non-metallic material to be engraved is covered with a hollow copper mold, and then a CO2 laser beam is used to scan the copper mold quickly to carve a complex pattern on the material. The carving objects are wood, acrylic, leather and paper. In addition, it can also be applied to carving unique handicrafts, such as bamboo carving, cork relief, shell relief and so on. In recent years, we have transformed to use sealed CO2 laser to directly use scanning galvanometer to make small and varied gift carving, so as to improve the added value of products.

The garment and footwear industry has been leading the way for more than ten years. It is also an early successful example of introducing foreign low-power CO2 laser processing or using self-produced low-power CO2 laser processing. It mainly uses 50 Watt laser to cut the mark plate and shoe pattern for making clothes. It is only used for development or a small number of diversified production, so the number is limited. There are also a small number of about 150 watts CO2 laser directly used for leather clothing, leather goods and other production. In addition, the computer embroidery industry uses laser and CCD sampling to directly cut off many patterns embroidered on a large sheet. However, with the two industries moving out and shrinking, the application of CO2 laser in this field has not increased. However, the use of low-power CO2 laser to cut the thin bark for decoration on furniture or ornaments continues to grow, mainly combined with modeling design and later stage production, with high added value.

Due to the rapid development of CO2 laser abroad, low-power CO2 laser adopts sealed structure, and the quality is getting better and better. Therefore, in addition to the above processing industry, there are many such CO2 lasers in other imported application systems, which are used in perforation, printing industry, rapid prototyping, lens trademark and ceramic substrate processing, etc., and their application potential is not small.

CO2 laser with output less than 200W is more than enough for cutting some non-metallic thin materials. In addition to the common use of the above-mentioned industry, there are still many special materials in the industry that can be considered to be replaced by laser processing, such as acrylic model making in the construction industry and hard plate pattern of wedding album cover. Its characteristics are small and complex, but they can all be cut by CO2 laser. The cutting of mica sheet, fiber cloth in bulletproof vest, nylon safety belt and some other special materials such as FRP, ABS, Teflon, asbestos and rubber are all precedents of laser processing in foreign countries, but it is necessary to pay special attention to the emission of gas generated during cutting

2.2 application of medium and high power (200w-1600w) CO2 laser

At present, medium and high power laser is the mainstream of CO2 laser processing equipment. It is mainly used in sheet metal substitute industry, and a small number of machines are production equipment used by factories. At present, nearly one third of such laser machines are recently introduced, which shows that CO2 laser with such power is in the stage of rapid growth. The main application of medium and high power CO2 laser equipment is sheet metal cutting, most of which are operated in the form of OEM. The processing object is wide, the processing type is many, several kinds of application more or special examples are introduced below.

2.2.1 wood knife mould industry

CO2 laser is used to cut the grooves of various complex and repeated patterns with width of about 0.6 mm on the wood board, and then a sharp blade is installed to make the rolling cutter. This is a very important part in the production process of cutting all packaging cartons, plastic injection molding, styrofoam appliances and soft circuit boards, and has a good application prospect.

2.2.2 cutting of various machine parts

In fact, all kinds of machine parts with a certain thickness or complex shape can be processed by laser instead of the traditional processing method. Although the processing cost may be higher (some may not be certain), it can save a lot of manpower and improve product quality.

2.2.3 auto sheet metal cutting

The automobile sheet metal formed by die rolling is a three-dimensional shape, which is difficult to reprocess. If the five axis CO2 laser processing machine is used to cut the blank holder and excavate the internal holes, the advantages of laser processing can be fully demonstrated. At present, there are several domestic factories specializing in the production of sheet metal for automobile repair, and the imported five axis CO2 laser processing machine is used for this processing. But this kind of machine is still in the stage of high price. If we can reduce the price in the future, many domestic manufacturers will introduce this kind of machine.

2.2.4 sheet metal cutting of computer and electrical case

The sheet metal cutting of computer case, as well as the sheet metal cutting of various machine control boxes and cases, are the most important processing objects. In particular, some products have low output, complex shape, short product life cycle, and most of the sheet metal cutting that can not be cost-effective, such as electric toy case, vending machine case, power distribution panel, etc. There are also some processes that have been opened but need to be changed on the formed sheet metal after the product design is changed.

2.2.5 cutting of special materials

Because the laser can be used for non-contact cutting, the cutting seam is narrow and does not affect the peripheral material, so it is widely used in the advertising and construction industry. It is used for cutting mirror stainless steel or general stainless steel plate, such as signboard, sculpture, elevator control panel, kitchen utensils, circular saw blade, acrylic, spring gasket, and electronic parts less than 2mm Copper plate, some metal mesh plate, steel pipe, tin plated iron plate, lead plated steel plate, phosphor bronze, electric wood plate, thin aluminum alloy, quartz glass, silicon rubber, alumina ceramic sheet less than 1 mm, titanium alloy used in aerospace industry, etc. With the evolution of the industrial form, the sheet metal processing object is more and more complex and diverse, the traditional punching machine function can not meet the requirements, and the wire cutting speed is too slow. The processing function of CO2 laser just makes up for their lack, which is also the main reason for the continuous and rapid increase of the introduction speed of CO2 laser processing machine in recent years.