With the continuous development of laser processing technology, laser cutting is playing an increasingly important role in more and more fields. This paper introduces the current development status, trends, market application status, and prospects of high-power laser cutting technology at home and abroad, and proposes the technological development direction of China's high-power laser cutting industry.
1 Introduction
Laser processing technology is a composite advanced manufacturing technology that integrates optics, mechanics, electronics, materials processing, and testing. Combined with modern CNC technology, it forms highly efficient automated processing equipment that can overcome many technical bottlenecks that traditional manufacturing methods cannot achieve, playing an irreplaceable role in pillar industries of the national economy such as energy, transportation, steel metallurgy, shipbuilding and automobile manufacturing, electronics and electrical industries, and aerospace.
Currently, industries such as automotive, shipbuilding, aviation, aerospace, steel, and energy equipment urgently need laser cutting equipment, especially high-end equipment. Therefore, improving my country's laser cutting equipment manufacturing level is crucial. This will not only meet domestic market demand and break the foreign technological monopoly in this field, but also promote the advancement of my country's laser cutting technology. Achieving higher speed, higher precision, and intelligent laser cutting will be the goal of CNC laser cutting technology development.
2. The Significance of Developing the CNC Laser Cutting Machine Industry and Its Market Analysis
2.1 The Significance of Developing the CNC Laser Cutting Machine Industry
In the development and manufacturing of high-power CNC laser cutting equipment, after more than a decade of development, my country's laser cutting technology and equipment have grown from nothing to a certain industrial scale. In 2007, the sales of large-scale laser cutting equipment in China reached 1.5 billion yuan, basically dominating the domestic market for low- and mid-range products, with some products exported. However, compared with developed countries such as the United States, the European Union, and Japan, my country's laser cutting equipment is still at the low-end product stage, and most core technologies, such as high-power lasers, laser-specific control systems, laser beam transmission control, and proprietary laser cutting technologies, still rely on imports. Currently, internationally renowned companies such as TRUMPF (Germany), Bystronic (Switzerland), and PRIMA (Italy) have developed high-power, large-format, high-speed, flying-beam, multi-dimensional, and CNC automated laser cutting machines. In the field of high-end laser cutting systems, my country lags far behind international advanced levels, with products basically dependent on imports, requiring billions of yuan annually to import related technologies and equipment from abroad. For example, in the shipbuilding industry, the import of laser cutting equipment for medium and thick steel plates, 3D laser cutting equipment, and non-ferrous metal laser cutting equipment is expensive, has long order cycles, and lacks timely after-sales service, severely hindering the development of China's national economy. Furthermore, foreign exports to my country in this field face clear restrictions, employing a licensing system that strictly prohibits the use of this technology in military, aerospace, and other fields. Therefore, my country urgently needs to break through this technological barrier.
With the rapid development of my country's shipbuilding, automotive, aerospace, steel, and power generation equipment industries, the center of global manufacturing has shifted to my country. The annual growth rate of demand for complete sets of CNC laser cutting equipment in my country has reached over 50%. CNC laser cutting technology, with its flexibility and adaptability, is gradually replacing traditional processing methods in the thin plate processing field. Addressing the urgent need for laser cutting equipment in industries such as automotive, shipbuilding, aviation, aerospace, steel, and energy equipment, this project aims to overcome technical challenges such as the bed mechanical design of large-format, high-precision CNC laser cutting machines, linear motor drives and related motion systems based on high-speed cutting, 5-axis linkage 3D laser cutting technology, high-power beam transmission technology, CNC cutting software, and thick plate laser cutting technology. It also seeks to solve core technologies such as high-power lasers, laser transmission control, precision machine tools, and CNC systems. Developing high-speed, high-precision laser cutting machines, large-format thick plate laser cutting machines, 3D CNC laser cutting machines, and aerospace non-ferrous metal laser cutting machines are of great significance in breaking the monopoly of foreign manufacturers in this field, achieving import substitution, saving foreign exchange reserves, meeting domestic market demand, and actively promoting the rapid and healthy development of my country's key industry equipment manufacturing sector. In addition, it can drive the extension and development of related industrial chains, and vigorously promote the technological progress and industrial upgrading of upstream industrial chains such as high-power lasers, optical components, light guide systems, CNC systems, electrical control systems, precision machining, precision instruments, electronic components, and computer software.
2.2 Market Application Status and Future Prospect Analysis of CNC Laser Cutting Machines
The global cumulative number of high-power CNC laser cutting equipment sets has reached approximately 35,000 units, while my country currently owns only about 1,500 units. With the rapid development of the equipment manufacturing industry, my country's CNC laser cutting equipment market has entered a period of rapid growth, with an annual growth rate exceeding 50%. Application industries include: automotive, shipbuilding, aerospace, nuclear industry, machinery manufacturing, steel, textiles, petroleum, and laser processing centers.
At the 2006 National Laser Processing Academic Conference, experts believed that by the end of the 11th Five-Year Plan period, my country would need at least 1,500 sets of high-power CNC laser cutting machines annually, and by the end of the 12th Five-Year Plan period, the market demand for high-power CNC laser cutting machines in my country would reach 10,000 sets. In addition to general-purpose laser cutting machines, the demand for high-performance laser cutting systems such as high-speed and high-precision laser cutting machines, large-format thick plate laser cutting machines, three-dimensional CNC laser cutting machines, and aerospace non-ferrous metal laser cutting machines is also increasing day by day.
In overseas automobile production, 3D laser cutting machines are widely used for precise edge trimming of body panels, door panels, and other components. High-quality automated welding is then performed using laser welding robots, ensuring product quality and achieving extremely high production efficiency. In prototype development and small-batch production, highly flexible 3D laser cutting replaces a large number of punching and trimming molds, saving significant amounts of molds and greatly shortening the development cycle of new models. In Europe, almost all automobile manufacturers use laser processing in automobile research, development, and production. The breadth and depth of laser manufacturing technology applications in automobile manufacturing have become an important indicator of the automotive industry's advancement. Some domestic automobile manufacturers have already introduced laser cutting and laser welding production lines, and other companies also have plans to introduce them in their future development plans. 3D laser cutting machines play a crucial role in accelerating the development of new models.
Developing high-precision 3D laser cutting machines is of significant strategic importance for improving my country's aerospace technology and equipment level. The demand for high-performance laser cutting machines is even more urgent for national defense and military equipment. For example, the application of 3D laser cutting machines in the machining of curved surfaces of helicopter propellers can greatly shorten product prototyping time and improve component performance.
In the global market, laser cutting machines are developing towards higher power, larger format, and thicker plate cutting. Cutting and welding are the most fundamental processing techniques in the shipbuilding industry. Currently, my country generally uses flame cutting and plasma cutting for shipbuilding steel plates. Due to limited precision, especially for special materials such as decks and hulls, many large foreign shipyards widely adopt large-format, thick-plate laser cutting machines. Domestic shipbuilding companies have begun purchasing equipment, especially for special-purpose vessels, where laser cutting has become an essential processing method. It is expected that the production demand in this application industry will be enormous in the next 5-10 years. With the advent of the "precision shipbuilding" era, high-power CO2 laser cutting technology and equipment are becoming increasingly widespread in the shipbuilding industries of advanced countries.
Large-format thick plate laser cutting machines are also in urgent demand in other important industries, such as cutting aerospace engine rotor hubs, laser cutting of hot-rolled steel billets in the steel metallurgy industry, precision cutting of thick armor in tanks and armored vehicles, and precision cutting of generator rotors in power generation equipment.
With the advancement of major projects in my country's railway, highway, water conservancy, hydropower, energy, mining, and construction industries, the demand for construction machinery in my country is projected to exceed 200 billion yuan by 2015. Large-format thick steel plate laser cutting machines will be widely used in my country's construction machinery industry. In 2007, a well-known domestic heavy machinery company tendered for 27 3m×30m large-format 20mm thick steel plate laser cutting machines. Because no domestic laser manufacturers met the technical requirements, all orders were won by foreign manufacturers. Another heavy machinery company requested 6 3m×30m large-format 20mm thick steel plate laser cutting machines, all of which were also won by foreign manufacturers. The total contract value for these two companies alone reached 200 million yuan.
The global laser manufacturing technology is developing rapidly, and the gap between my country and international laser technology levels has widened. High-end laser processing equipment is almost entirely dependent on imports, resulting in foreign laser manufacturing equipment holding a 70% market share in my country. It is estimated that within the next 10 years, my country's market demand for these high-performance laser cutting systems will reach 10 billion yuan. This urgent and enormous market demand reflects that laser processing has permeated all important sectors of the national economy and is also influencing breakthroughs in key technologies such as national defense and aerospace. Our goal is not only to fill the current domestic gap in this product but also to address core technical issues across multiple levels in the laser processing field, such as laser CNC, new structures for laser machine tools, and the technical bottlenecks in high-quality laser processing.
3. Current technological status, development trends, and common key technologies that need to be overcome.
3.1 Current Status and Development Trends of CNC Laser Cutting Technology Abroad
Currently, leading international manufacturers of laser cutting equipment include: TRUMPF (Germany), BYSTRONIC (Switzerland), PRIMA (Italy), WHITNEY (USA), and TANAKA (Japan). Their representative technologies are shown in the table below. These internationally renowned companies have successively developed high-power, large-format, high-speed, flying-beam laser cutting machines, enabling three-dimensional machining and CNC automation, and are launching new models every year. For example, Bystronic launched a 2g acceleration high-speed machine tool in 2002 and a 3g acceleration machine tool in 2007, demonstrating the rapid pace of technological development.
With the increasing popularity of laser cutting, the market demands further improvements in cutting efficiency (high-speed cutting), reduced standby time (automatic loading and unloading systems), expanded applications (towards three-dimensional cutting, thick plates, and high-reflectivity materials), and reduced operating costs (lower power consumption). International trends in laser cutting technology development include:
3.1.1 High Speed
In terms of equipment operating speed, many companies are currently competing to develop high-speed, high-precision cutting machines to replace mechanical punch presses. For example, the BYSPEED model launched by Bystronic Laser GmbH in Switzerland has a cutting speed of up to 40m/min and an acceleration of 3g. It can cut 20mm stainless steel, 12mm aluminum alloy and 6mm copper, etc. Its power consumption is only 60kW and the machine's effective utilization rate can reach 95%. In terms of thin plate processing efficiency, it is comparable to punch presses.
Prima Industries' latest SYNCRONO machine tool employs a unique and novel design concept, introducing the idea of parallel machine tools for the first time in laser cutting design. It combines two machine tools into one: a small cutting head with extremely high dynamic performance and ultra-light weight, and a large, conventional machine tool responsible for movement over a wide machining range. The two are perfectly synchronized through CNC control, achieving optimal processing efficiency. Due to the extremely light weight of the cutting head, it achieves very high dynamic performance. The machine tool also employs a special dynamic balance design and a specially optimized drive control algorithm, ensuring smooth trajectories and completely eliminating vibration during high-speed movement. This design results in the SYNCRONO machine tool achieving unimaginable acceleration, reaching up to 6g during cutting, and capable of cutting 1000 holes per minute—almost twice as fast as the fastest cutting machine currently on the market. At the same time, its operating costs are significantly lower than its competitors. In fact, SYNCRONO is ushering in a new era of laser cutting.
3.1.2 Multiple degrees of freedom
Laser cutting machines are widely used in the processing of complex curved surfaces and workpieces, such as laser cutting robots, 2.5D laser cutting machines specifically for pipe cutting, and 3D fiber optic laser cutting machines.
Previously, 3D laser cutting machines could only cut automotive interior parts and could not process metal stampings. Prima Industrial has creatively integrated capacitive sensors into 3D laser cutting equipment, enabling the machine tool to automatically adapt to errors caused by the elastic deformation of stampings. This makes 3D laser cutting technology a truly precise and flexible processing method for automotive body manufacturing, widely used in the automotive, aerospace, construction machinery, mold making, fitness equipment, sheet metal processing and other manufacturing fields.
3.1.3 Large-format, thick plates
Currently, the concept of "precision shipbuilding" has emerged internationally, and high-power laser cutting technology is widely used in shipbuilding in countries and regions such as the United States, the European Union, Japan, and South Korea. At present, mainstream large-format laser cutting machines abroad generally adopt an airborne laser structure, with a processing area of 3m × 25m and a cutting plate thickness of up to 40mm, and are increasingly used in the shipbuilding and naval vessel industries.
3.1.4 Intelligentization
Furthermore, by combining lasers with computer numerical control technology, advanced optical systems, and high-precision and automated T-part positioning, automatic material feeding, cutting process database, remote diagnosis, and remote control can be integrated into one unit. By combining the functional components of laser cutting with other processing methods, multi-functional processing machines such as laser punching machines can be manufactured, which better meet the needs of factories for complex and efficient processing. It combines the multi-functionality of laser cutting with the high speed and efficiency of other processing methods, and can simultaneously complete cutting, drilling, marking, scribing, and forming.
3.2 Development Trends of CNC Laser Cutting Technology in China
In recent years, my country has made rapid progress in the field of CNC laser cutting technology and equipment. The power of carbon dioxide lasers has reached 4kW, and the processing area can range from 3015 to 6030. Various optical path designs have been maturely applied, and linear motor servo systems are commonly used in terms of drive. Domestic CNC laser cutting equipment has already achieved strong market competitiveness.
With the rapid popularization of laser cutting technology, the market space is constantly expanding. The development focus of CNC laser cutting equipment in my country should be on the following areas:
3.2.1 Develop high-speed, high-precision CNC laser cutting equipment
Master the design and manufacturing technology of motion systems with acceleration above 3g and the design and manufacturing technology of high-precision and high-speed machine tool motion systems. Positioning speed is 120-180 m/min, cutting speed is 50-80 m/min, cutting surface roughness is less than 6.3μm, cutting head positioning accuracy is ±0.02 mm/m, repeatability is 0.01 mm/m, and when used for high-speed laser hole cutting, the cutting speed reaches 1000 holes/min.
3.2.2 Develop high-precision three-dimensional laser cutting equipment
Master the design and manufacturing technology of 3D laser cutting machines, the design and manufacturing technology of 3D laser cutting heads, and the 3D laser cutting process; develop supporting 3D CAD/CAM software systems to achieve laser cutting of complex curved surfaces. Positioning accuracy ≤ ±0.05mm, repeatability ≤ ±0.015mm. Rapid traverse speed ≥ 25m/min; A/B axis rotation range 360°/±135°, rotation accuracy ≤ 0.015°, repeatability ≤ 0.005°.
3.2.3 Develop large-format thick plate laser cutting equipment
Mastering long-range laser transmission technology, thick plate cutting technology, and high-power laser optical path design and manufacturing technology, we can achieve large-format laser cutting of thick plates. The laser cutting machine tool has an X/Y/Z travel of >130000mm/6000mm/150mm, positioning accuracy ≤±0.05mm, repeatability ≤±0.015mm, rapid traverse speed ≥25m/min, and can cut plates up to 40mm thick.
3.2.4 Develop specialized laser cutting equipment for special industries
Master the design and manufacturing technology of laser cutting machines for special materials and special processing needs, and complete the cutting process of aluminum alloy, titanium alloy, magnesium alloy and copper alloy from 1-10mm.
3.3 Key Common Technologies for CNC Laser Cutting That Need to Be Overcome
3.3.1 Mechanical Structure Design and Drive Technology of Laser Cutting Machine
Laser cutting machine beams come in various types, including single cantilever, gantry, and inverted gantry, requiring high rigidity and stability in the machine structure. The beam design must be lightweight and flexible, meeting the requirements of smooth movement and high precision during high-speed laser cutting. These are fundamental to achieving precision laser cutting.
3.3.2 CNC Technology for Laser Cutting Machines
Combining the unique characteristics of laser cutting, and based on a stable and reliable general-purpose CNC system, a laser cutting control system with independent intellectual property rights has been developed through secondary development. It possesses laser-specific control functions, such as laser power ramp adjustment, Z-axis floating function control, and automatic focusing function; excellent machine tool motion control performance at high speeds; remote diagnostic and control functions; integrated machine tool control (laser control, gas path control, and optical path control); and meets the calculation and judgment requirements for large-format laser cutting. The human-machine interface is user-friendly, with voice prompts, facilitating operation and maintenance.
3.3.3 High-power laser beam transmission and focusing technology
Beam quality is crucial for laser cutting quality, and key technologies include proprietary beam quality control, beam radius adjustment, beam waist compensation, and video beam calibration systems. The proprietary beam quality adjustment system includes an adaptive optics system to optimize beam shape. Beam radius adjustment enables the adaptive optics system to automatically maintain the beam focus point within the program. For example, when cutting low-carbon steel, it automatically outputs a very fine beam focus point, while when cutting stainless steel, it automatically outputs a wider focus point. Laser beams are not parallel; the spot diameter changes as the cutting head moves within the cutting range. To maintain good cutting quality, waist compensation is used to keep the spot diameter constant. The control system automatically adjusts the beam waist position to maintain the optimal spot size at the focal point. The video beam calibration system utilizes video technology and fine-tuning devices, allowing the operator to inspect the beam path without opening any covers, ensuring the accurate positioning of all optical lenses. The main advantages of this function are: first, safety: it does not require opening the optical path, avoiding the danger of contact with the laser during the optical path inspection process; second, reliability: the inspection process is fast and reliable, keeping the optical path system in the optimal cutting state; and third, simple maintenance: the target position can be viewed in real time, saving a lot of operations and allowing for faster maintenance and adjustment.
3.3.4 Proprietary Laser Cutting Technology
Laser cutting proprietary technologies include: edge monitoring, capacitance height tracking, cutting monitoring, and penetration detection. Edge monitoring technology positions the cutting head at the appropriate edge of the sheet material, automatically monitoring its position and direction. Penetration detection technology uses the same sensor to determine whether the beam has penetrated the sheet material, achieving the highest quality penetration while saving time. Cutting monitoring technology allows the machine to perform cutting operations normally even when unattended. If cutting malfunctions, the cutting monitoring system can identify the problem, and the system software will determine the cause and take appropriate action, including stopping, reversing, and adjusting the power for better results. Capacitor height tracking technology uses a capacitor system. High-frequency signals are transmitted to the cutting head through the capacitor system of the metal component at the nozzle. As the distance between the workpiece and the metal component of the cutting head changes, the frequency changes proportionally. The CNC controller uses this information to adjust the Z-axis to its optimal position.
3.3.5 Dedicated CAD/CAM software system for laser cutting
To facilitate graphic conversion in laser cutting, a specialized CAD/CAM software system needs to be developed. This system converts geometric information obtained from the CAD system into NC code, which is then transmitted to the CNC system via USB or a communication system for normal cutting operation. The NC code generated by the CAD/CAM software system possesses all the unique functions of laser cutting, making the programming of complex parts simple and smooth, and facilitating editing and modification.
3.3.6 Design and Manufacturing of High-Power Laser Cutting Heads for Thick Plates
When developing a long focal depth high-power laser multidimensional stereoscopic cutting head, the cutting head should be equipped with a dual focusing lens assembly, a sensitive and reliable Z-float component, a good water cooling device and an air cooling device, and be able to withstand an auxiliary gas pressure of about 2533 kPa to meet the requirement of a cutting thickness of 30-40 mm.
3.3.7 Research on Laser Cutting Technology
Through extensive cutting process experiments, a cutting process database has been established, including materials, environment, and process parameters such as laser power, auxiliary gas pressure and type, cutting speed, focal point position, and cutting start position. Especially for processes such as curved surface cutting, titanium alloy cutting, and thick plate cutting, the operator only needs to enter the basic parameters and information according to the prompts in the dialog box, and the system will automatically call up the database data to complete the cutting parameter settings.
4. Conclusion
CNC laser cutting is an ideal cutting and processing method, representing the development direction of modern metal processing technology. CNC laser cutting equipment has extremely broad market demand both domestically and internationally. While my country lags behind foreign countries in CNC laser cutting technology and equipment, it has developed rapidly in recent years. Future development should focus on high-level research and development, particularly in high-speed, high-precision laser cutting, large-format laser cutting, 3D laser cutting, and laser cutting of special materials, to achieve industrialization and meet the ever-growing market demand.
