Laser beam has a series of advantages such as good monochromaticity, high energy density, good spatial controllability and time controllability. At present, it has been widely used in materials processing and other fields. Laser processing industry includes automobile manufacturing, aerospace, electronics, chemical industry, packaging, medical equipment and so on. The combination of laser processing technology and computer numerical control technology has become the key technology of industrial production automation, which has incomparable advantages over ordinary processing technology. For example, laser machining is non-contact, fast and noiseless, which can achieve the purpose of high-precision machining of various complex shapes, and there is no "tool" wear in the usual sense, and there is no need to replace the "tool head". Laser welding of plastics 1. Advantages of plastic laser welding With the increasingly wide application of plastics in the design and manufacture of parts in automobile, medical equipment and electronic industry, high-power fiber laser plastic welding system can completely meet the fast, effective and clean use of plastics in plastic product processing, and high-power fiber laser plastic welding system can completely meet the fast, effective and clean plastic welding method in plastic product processing. At present, the commonly used plastic welding technologies in the domestic market mainly include vibration friction welding, hot plate plastic welding and ultrasonic welding. It is mainly used to connect sensitive plastic products (including circuit boards), plastic parts with complex geometric shapes and plastic products (medical devices) with strict cleanliness requirements. Fiber laser welding plastic technology has the following advantages: (1) can produce accurate, firm and sealed (airtight and watertight) welding, with less resin degradation and less fragments. (2) It is easy to control and has good adaptability, and can weld workpieces with small size or complex shape and structure. (3) The vibration stress and thermal stress of the product are greatly reduced. (4) Many different materials can be welded together. Laser plastic welding technology has been applied in developed countries such as Europe and America, but it is still blank in China. 2. Welding method of plastic laser welding The basic principle of plastic laser welding is to clamp two kinds of plastics together under low pressure, and the laser passes through one product and then is absorbed by the other product. Products that absorb laser energy convert light energy into heat energy, which melts at the plastic contact surface to form a welding zone. The commonly used welding methods mainly include: a. The laser beam scans quickly along the weld to achieve the purpose of welding. B, shaping the laser beam through an optical element, and generating heat at the welding seam. C, radiation mask welding, the laser beam only heats the part of the product that is not covered by the mask, so that complex welds can be welded quickly. D, the laser beam is fixed, and the plastic workpiece is placed on the multi-dimensional moving workbench controlled by the program. Third, the application of high-power fiber laser in shipbuilding industry 1. Advantages of laser processing technology in shipbuilding industry The main advantages of laser processing in shipbuilding industry are: (1) The self-weight of ships is increasing day by day, which requires the use of very thin flat plates, and laser welding avoids the thermal influence during processing; (2) Laser can use flexible output modes such as optical fiber, so the processing of workpieces with large surface sizes such as decks and hulls can be independent of the size of the workbench. (3) Non-contact, fast, stable and high degree of automation, which greatly reduces the shipbuilding cost and time. 2. Development status at home and abroad: Laser processing technology is widely used in major shipyards in Europe, America and Japan. At present, the United States, Europe and other regions are developing high-power fiber laser industrial processing equipment, and processing equipment with 2KW and 6KW output is under secondary research and development. China has developed a series of medium and small power industrial fiber laser equipment, but the industrial processing application of high power fiber laser is still blank, and laser processing technology is almost not used in China's shipbuilding industry. 3. Advantages and prospects of high-power fiber laser in shipbuilding industry Fiber laser has attracted much attention in laser field in recent years. In the processing field, fiber laser has a tendency to rapidly replace traditional YAG and CO2 lasers. It is generally believed that high-power fiber laser will be the third generation of the most advanced industrial processing laser. Fiber laser has many unique advantages and good beam quality. Small size, light weight and maintenance-free; Air cooling is simple and easy to operate; Low operation cost, and can be used in industrial environment; Long service life, high machining accuracy and high speed; The electric energy conversion efficiency is high, and intelligent, automatic and flexible operation can be realized. Based on the above advantages, its application field has been extended to laser cutting and laser welding of metal and nonmetal materials in automobile manufacturing, shipbuilding and aviation manufacturing.