4.Comparison of YAG laser and CO2 laser

YAG laser output wavelength of 1.06um, just than CO2 laser wavelength 10.06μm smaller than an order of magnitude, so that it coupled with the metal high efficiency, good processing performance, YAG laser can be coupled with the fiber, with time division and power division multiple system Can easily transfer a laser beam to a number of stations or remote distance station, to facilitate the realization of flexible laser processing; YAG laser pulse and can work in two ways, the pulse output can be Q-switched and clamping technology Short pulse and ultrashort pulse, so that its processing range is larger than the CO2 laser; YAG laser compact structure, light weight, easy to use and reliable, low maintenance requirements, the price is relatively low, so the application of promising.

The main drawbacks of YAG lasers are:
1. Its conversion efficiency is low, only 1-3%, which is about an order of magnitude lower than the efficiency of CO2 lasers;
YAG laser rods have an internal temperature gradient during working, which will cause thermal stress and thermal lens effect, which limits the average power and beam quality of YAG laser to further improve;
3. YAG laser output power per watt cost more expensive than CO2 laser.
4. Most of the current output power of 600W or less, the output energy is small, mainly used for drilling and spot welding and sheet cutting.

5.Trend Analysis of Laser Cutting Equipment Replacing Conventional Processing Technology

Laser cutting is a process of sheet metal processing revolution, is the sheet metal processing in the “processing center.” Laser cutting a high degree of flexibility, cutting speed, high production efficiency, short production cycle, for customers to win a wide range of markets. Laser cutting without cutting force, no deformation processing; no tool wear, good material adaptability; whether simple or complex parts, can be used once a laser precision rapid cutting; its narrow cutting, cutting quality, high degree of automation, Simple, low labor intensity, no pollution; can achieve automatic cutting nesting, nesting, improved material utilization, low production costs, good economic returns. The technology of the effective life of a long, currently in foreign 2 mm below most of the sheet metal laser cutting, many foreign experts agree that the next 30-40 years is the golden age of laser processing technology development (sheet metal processing development direction) In recent years, China’s sheet metal processing technology and product quality have been rapid development, and processing enterprises to gradually spread the use of laser Cutting Machine are inseparable.

In the sheet metal industry, laser cutting machine in a large range of alternative CNC punch, laser cutting machine than the advantages of CNC punch has the following six aspects:
1. Do not need to open mode, only the computer will map to make the product immediately Can come out, that can quickly develop new products, but also cost savings.
2. Laser cutting machine with automatic tracking system, so that the completion of plane cutting, but also to complete a variety of uneven surface of the cutting.
3. The complex process requires CNC punch Difficult to complete, laser cutting can do.
4. To complete a variety of complex structure of the processing, as long as the computer can draw any image, the machine can complete the processing.
5. Forming the box to increase the processing of pores, CNC punch can not handle, metal laser cutting To solve .
6, the surface is very smooth, high-grade products, CNC punch is difficult to do.

As the laser cutting machine has many advantages, with the development of metal processing industry, the advantages of metal laser cutting machine more and more obvious, so the proportion of laser cutting machine position is also growing.

Three-dimensional laser cutting in improving product quality, production efficiency, shorten product development cycle, reduce labor intensity, saving raw materials and other obvious advantages. Therefore, despite the high cost of equipment, one-time investment, there are still a lot of cars, aircraft manufacturers purchased three-dimensional laser processing machine, some universities have purchased the appropriate equipment for scientific research, three-dimensional laser technology is bound to play in China’s manufacturing industry With a growing role.

Laser cutting is the most widely used in automotive body design and manufacturing, mainly used to develop new models, on-line cutting, deformation car production, such as cutting car parts, body panels cut holes, trimming, cutting the steering wheel hole, Wind panels, roof cover bracket holes, airbag components, hydraulic molding components. BMW, Mercedes-Benz, Fiat, Volvo, Volkswagen, Nissan and other companies have for the body processing of five-axis laser processing machine. Three-dimensional laser cutting is also useful after assembly of the body, such as opening the luggage rack with the hole, the top cover slide holes, antenna mounting holes, modify the wheel fender shape. In aerospace, the technology is mainly used for forming stainless steel, Inconel alloy, titanium and aluminum aircraft parts for drilling, cutting and dressing.

Laser three-dimensional cutting technology is also widely used in mold manufacturing, sculpture, oil industry and other industries. In the printing industry, laser engraving cutting machine using laser energy and high efficiency, through the process control of the rubber plate ablation, to create a printing plate is not only low cost, and carving fine, high quality; the use of laser High-energy characteristics of the knife template deep ablation, you can create a variety of high-precision knife to die. In the field of mold manufacturing, can be used for processing mold, try to mold, mold manufacturing. The combination of mold CAD and laser cutting can be used to manufacture complex structures, such as deep holes, holes, hollow bodies and complex cooling channels. The thin steel plates are cut by laser and then superimposed into die or punch. In the oil industry, this technique is used to process slotted screens.

Many shipbuilding manufacturers in the United States, Europe and Japan have long put high-output CO2 laser cutting machine technology for shipbuilding, and has been successful.

These years, “precision shipbuilding,” the formulation is familiar, to really do this, just to CNC cutting point of view, the current domestic shipyard equipment is clearly not up to technical requirements, people’s attention naturally to the cutting of a higher precision Of laser cutting, no doubt this will become CNC laser cutting machine into the driving force behind China’s shipbuilding industry. Optoelectronic technology with each passing day, so that the laser cutting operation costs (yuan / kW) greatly reduced, together with the manufacturers to seize the initiative for the fierce market competition will inevitably lead to lower prices of laser cutting machine, and ultimately to Comprehensive economic benefits and CNC Plasma Cutting Machine competition by China’s shipbuilding industry gradually to understand and accept.

It can be said that laser cutting technology has penetrated into all areas of the national economy, can be expected in the next few years, laser cutting technology will be a higher speed in the manufacturing industry to promote the use of China’s manufacturing industry to the direction of the development of sophisticated important contribution.