Current and development trend of precision and ultra-precision machining

First, the concept and scope of precision and ultra-precision machining Generally, according to the processing precision, machining can be divided into three stages: general machining, precision machining and ultra-precision machining. At present, precision machining refers to processing technology with a processing accuracy of 1~0.1μ; m ​​and a surface roughness of Ra 0.1~0.01μ; m, but this limit is constantly changing with the advancement of processing technology, today's precision machining May be the general processing of tomorrow. The problems to be solved by precision machining are: machining accuracy, including geometrical tolerance, dimensional accuracy and surface condition; second, processing efficiency, some machining can achieve better machining accuracy, but it is difficult to achieve high machining efficiency. Precision machining includes micromachining, ultra-fine processing, finishing processing and other processing technologies. Traditional precision machining methods include abrasive belt grinding, precision cutting, honing, precision grinding and polishing.
a. Abrasive belt grinding is the processing of workpieces with abrasive fabrics with abrasives. It belongs to the range of grinding abrasives, with high productivity, good surface quality and wide application range.
b. Precision cutting, also known as diamond tool cutting (SPDT), is used for cutting machining with high-precision machine tools and single crystal diamond tools. It is mainly used for precision machining of soft metals such as copper and aluminum, which are not suitable for grinding, such as computer. Metal mirrors for magnetic drums, magnetic disks, and high-power lasers are 1 to 2 grades higher than normal cutting precision.
c. honing, the honing head composed of whetstone sand bar reciprocates along the surface of the workpiece under a certain pressure, the surface roughness after processing can reach Ra0.4~0.1μ; m, preferably to Ra0.025μ; m, It is mainly used to process cast iron and steel. It is not suitable for processing non-ferrous metals with low hardness and good toughness.
d. Precision grinding and polishing through the abrasive and machining fluid between the workpiece and the tool, the workpiece and the lap are mechanically rubbed together to achieve the required size and precision of the workpiece. Precision grinding and polishing can achieve the precision and surface roughness that can not be achieved by other processing methods for metal and non-metal workpieces. The roughness of the surface to be polished is Ra≤0.025μ; the thickness of the processed metamorphic layer is small, the surface quality is high, and the precision is ground. The equipment is simple, mainly used for the processing of flat, cylindrical surface, gear tooth surface and sealing parts with sealing requirements. It can also be used for the finishing of gauges, gauge blocks, fuel injectors, valve bodies and valve cores.
e. Polishing is a kind of micro-machining of the surface of the workpiece by mechanical, chemical and electrochemical methods. It is mainly used to reduce the surface roughness of the workpiece. Common methods include: manual or mechanical polishing, ultrasonic polishing, chemical polishing, and electrochemistry. Polishing and electrochemical mechanical composite processing. After manual or mechanical polishing, the surface roughness of the workpiece is Ra≤0.05μ; m, which can be used for polishing of plane, cylinder, curved surface and mold cavity. Ultrasonic polishing processing accuracy 0.01~0.02μ; m, surface roughness Ra0.1μ; m. The surface roughness of the chemical polishing process is generally Ra ≤ 0.2 μ; m. Electrochemical polishing can be increased to Ra 0.1~0.08μm.
Ultra-precision machining is the processing of extremely high shape accuracy and surface finish on ultra-precision machine tools by using the strictly constrained relative motion generated between the part and the tool. The current ultra-precision machining refers to a processing technique in which the dimensional accuracy of the machined part is higher than 0.1 μm, the surface roughness Ra is less than 0.025 μm, and the resolution and repeatability of the machine tool positioning accuracy is higher than 0.01 μm. Micron processing technology and is developing towards nanoscale processing technology.
Ultra-precision machining includes micromachining, ultra-fine machining, finishing, finishing and other processing technologies. Micro-machining technology refers to the processing technology for manufacturing small-sized parts; ultra-fine processing technology refers to the processing technology for manufacturing ultra-small-sized parts. They are proposed for the manufacturing requirements of integrated circuits. Due to the small size, the precision is cut off. The absolute value of the dimension is expressed instead of the ratio of the processed dimension to the dimensional error. Finishing generally refers to a processing method that reduces the surface roughness and improves the mechanical properties of the surface layer. It does not focus on improving the processing accuracy. Typical processing methods include honing, grinding, super finishing and chipless processing. In fact, these processing methods not only improve the surface quality, but also improve the processing accuracy. Finishing processing is a new term proposed in recent years. It corresponds to finishing, which means reducing the surface roughness and improving the mechanical properties of the surface layer, as well as improving the processing accuracy (including size, shape, Positioning accuracy).

Second, the development status and application of precision machining
1. Development status and application of precision forming processing Precision casting forming, precision molding, plastic processing, and thin-plate precision forming technology are highly valued in industrialized countries, and a large amount of funds are invested in giving priority to development. In the 1970s, the US Air Force hosted the "Forging Process Modernization Program", which aims to modernize the important process of forging and use CAD/CAM more to reduce the manufacturing cycle of new forgings by 75%. In 1992, the US Department of Defense proposed the "Military Key Technology List", which includes isostatic forming technology, numerical control computer controlled spinning, plastic deformation and shear forming machinery, superplastic forming/diffusion joining process, hydraulic extension forming process, etc. Precision plastic forming process. In recent years, foreign countries have also developed "forging and blade precision forging process for large die forgings", "rapid solidification powder lamination process", "strong spinning process for large complex structural parts" and "difficult" "Superplastic forming process of deformed materials", "Advanced materials (such as metal matrix composites, ceramic matrix composites, etc.) forming process". China's superplastic forming technology is also used in the aerospace and machinery industries, such as satellite components, missiles and rocket gas cylinders in the aerospace industry. The superplastic forming method is used to manufacture the Qin alloy recovery tank of reconnaissance satellites. At the same time, the superplastic forming process of zinc, copper, aluminum and alloy is basically mastered, and the minimum forming thickness is up to 0.3 mm, and the shape is also complicated. In addition, precision molding technology has been widely used in foreign countries to manufacture weapons. Commonly used precision molding techniques, such as closed forging, precision forming using splitting principle, and isothermal forming, have been used in military production abroad. At present, the precision molding technology is still less applied in China, and the precision is also poor. The foreign precision is ±0.05-0.10mm, and the country is ±0.1-0.25mm.
2. Development status and application of hole processing technology In recent years, automobile, mold parts and metal processing have mostly adopted the production form centered on CNC machine tools. When performing hole processing, most of them use advanced equipment such as machining centers and CNC electric machine tools. High-speed, high-precision drilling processing has been put on the agenda. Regardless of the hole processing in any field, achieving high precision and high speed is an important competitive means to obtain user orders.
In recent years, with the advent of high-speed milling, cutting machining centering on milling tools is entering a high-speed and high-precision machining period. In the hole processing operation, high-speed steel twist drills are still widely used, but the gap between the processing precision and processing efficiency of various enterprises has gradually widened. The material of the high-speed cutting bit is mainly made of ceramic-coated cemented carbide. For example, when MAZAK and Mori Seiki manufacture the cast iron, the ceramic coated drill bit is used. In the processing of colored materials such as aluminum alloys, diamond-coated carbide drills, DLC coated carbide drills or drill bits with diamond sintered body teeth may be used. High-speed and high-precision hole machining In addition to precision machining of the hole by CNC cutting method, the hole can be processed with high precision by boring and reaming. With the high speed of the machining center spindle, the boring tool can be used to perform high-speed precision machining of the hole.
With the development of IT-related industries, the demand for parts and components of devices used in the optical and electronic industries has increased rapidly in recent years, and this growth has stimulated the rapid development of micro-shape and high-precision processing technology. Among them, the development and application of micro-hole processing technology is particularly eye-catching. Micro-hole processing has long been applied in the processing of printed circuit boards, etc., and a variety of materials to be processed, including steel, can be processed by small diameters with drill bits. At present, in the processing of small-diameter holes, the diameter of cutting with a drill can be as small as about φ50 μm. Holes smaller than φ50 μm are mostly fabricated by electrical machining. In order to suppress the occurrence of burrs, many researchers have proposed that ultrasonic vibration cutting can be used. At present, an ultrasonic vibration cutting mode with a wide range of applications and reasonable processes is being explored, including research on the adaptability of machine tools. With the smooth resolution of these problems, it is expected that the micro-deep hole machining with smaller diameter will be better realized in the future, and the machining accuracy will be higher.
3. Development status and application of special heat treatment The special heat treatment process is one of the key manufacturing technologies of the defense industry system. Vacuum heat treatment is widely used in aerospace structural parts treatment, such as carburizing or nitriding on the surface of gear structural parts, various alloys for missiles and spacecrafts, due to its unique non-contaminated beam, no oxidation, small deformation of the workpiece and wide application range. Or the stress relief, reinforcement or toughening treatment of steel parts. Typical structures such as instrument parts, transmission structures, fuel tanks, engine casings, etc.; more than 50% of US heat treatment furnaces are vacuum heat treatment furnaces. Vacuum heat treatment furnaces have been widely used in computer control. At present, vacuum chemical heat treatment and vacuum gas quenching heat treatment have been developed, including high pressure vacuum gas quenching, high flow rate vacuum gas quenching and high pressure and high flow rate vacuum gas quenching technology. In addition, laser heat treatment technology has been widely used in aerospace, aerospace, electronics, instrumentation and other fields, such as various complex surface parts, micro-components, parts requiring localized processing components, microelectronic devices, large-scale integrated circuits production and repair, Precision optical components, precision measuring components, etc.
4. Application of new technology of numerical control EDM
a. Standardized fixtures CNC EDM is a standardized fixture that uses fast clamping to ensure extremely high repeatability and without reducing machining efficiency. The standardized fixture is a fast and precise positioning process. Its use greatly reduces the clamping positioning time in the CNC EDM process and effectively enhances the competitiveness of the enterprise. There are currently EROWA in Switzerland and 3R devices in Sweden for fast and precise positioning.
b. Mixed powder processing method A method of processing in which a powder additive is mixed in an electric discharge machining liquid to obtain a glossy surface at a high speed is called a mixed powder processing. This method is mainly applied to complex mold cavities, especially precision machining of complex surfaces that are not convenient for polishing operations. It can reduce the surface roughness value of the parts, eliminate the manual polishing process, and improve the performance of the parts (such as life, wear resistance, corrosion resistance, mold release, etc.). The development of the mixed powder processing technology has made the mirror processing of precision cavity molds a reality.
c. Shaking processing method When EDM machining complex cavity, according to the shaking pattern of the processed part, the shape and accuracy of the shaking amount, the method of continuously shaking the electrode can be selected to obtain a more uniform surface roughness of the side and the bottom surface, and It is easy to control the processing size and achieve stable processing under small gap discharge conditions.
d. Multi-axis linkage processing method In recent years, with the development of the mold industry and IT technology, multi-axis linkage EDM technology has made great progress. The mold enterprise adopts the multi-axis linkage method to improve the processing performance. For example, the method of three-axis linkage of X, Y and Z is used in the case where the cleaning angle is feasible, that is, oblique processing, which avoids the discharge due to the small area of ​​the processing part. Unstable phenomenon. The processing of the mold latent rubber mouth can also be performed by oblique multi-axis linkage processing by designing the positioning of the electrode inclination. The multi-axis rotary system is combined with various linear motions to form a variety of composite motion modes, which can adapt to the processing requirements of different types of workpieces, expand the processing range of CNC EDM, and improve its comparative advantages and technical benefits in precision machining.
5. Development trend of precision machining technology The development trend of precision machining technology for the 21st century is reflected in the following aspects:
a. Precision The core of precision machining is mainly reflected in the requirements for dimensional accuracy, profiling accuracy and surface quality. The precision of the current precision EDM has been improved. The size processing requirements can reach ±2-3μm, the bottom corner R value can be less than 0.03mm, and the best machined surface roughness can be lower than Ra0.3μm. Through the use of a series of advanced processing techniques and processes, mirror processing can be achieved and EDM can be successfully completed in high-precision mold parts such as micro connectors, IC plastic packages, mobile phones, and CD cases.
b. Intelligentization Intelligentization is one of the development trends of manufacturing technology in the 21st century. Intelligent Manufacturing Technology (IMT) integrates artificial intelligence into all aspects of the manufacturing process. By simulating the intelligent activities of human experts, it replaces or extends part of the mental work in the manufacturing system. During the manufacturing process, the system can automatically monitor its operating status. External disturbances or internal excitations automatically adjust their parameters to achieve optimal conditions and self-organization capabilities. The new numerical control EDM machine adopts fuzzy control technology and expert system intelligent control technology. The fuzzy control technology is to monitor the state of the EDM machining gap by computer monitoring, automatically select the processing conditions that maximize the machining efficiency within the range of maintaining stable arc; automatically monitor the machining process to achieve the most stable control technology of the machining process. The expert system adopting human-machine dialogue mode can automatically create a machining program according to the processing conditions and requirements, and input the set value reasonably, and select the best processing condition combination for processing. Online automatic monitoring and adjustment of the processing process to achieve optimal control of the machining process. When the machining system detects the machining conditions, the input machining shape, electrode and workpiece material, machining position, target roughness value, electrode scaling amount, shaking mode, taper value and other indicators can be automatically calculated and configured. The application of expert system intelligence technology makes machine tool operation easier and requires less skill level for operators.
c. Automation The successful application of automation technology not only improves efficiency, but also guarantees product quality, and can also replace people to complete dangerous work. For large batch production automation, it can be completed by machine tool automation modification, application of automatic machine tools, special combination machine tools, and automatic production lines. Small batch production automation can be done by NC, MC, CAM, FMS, CIM, IMS, etc. In the implementation of the last automation technology, people will pay more attention to the role of people in the automation system. At the same time, automation began to target small and medium-sized enterprises, taking economic and practical as the starting point to meet the ever-increasing product diversification and individualization needs. The functions of automatic measurement and alignment, automatic positioning, and continuous machining of multiple workpieces of CNC EDM machine have already exerted its automation performance. The automatic operation process does not require manual intervention, which can improve the processing accuracy and efficiency. At present, the most advanced CNC EDM machine is equipped with an electrode library and a standard electrode fixture. As long as the electrode is loaded into the tool magazine before processing and the machining program is programmed, the entire EDM process can be automated. It runs almost without manual operation. The automatic operation of the machine tool reduces the labor intensity of the operator and improves the production efficiency.
d. Efficient The requirements of modern machining provide the best machining mode for CNC EDM technology, which requires a substantial increase in roughing and finishing efficiency under the premise of ensuring machining accuracy. For example, mobile phone casings, home appliances, electrical appliances, electronic instruments, etc., all require reduction of auxiliary time (such as programming time, electrode and workpiece positioning time, etc.), while reducing roughness, from the original Ra0.8μm to Ra0. 25μm, no need to carry out manual polishing after discharge. This not only shortens the processing time and saves the trouble of post-processing, but also improves the quality of the mold, which can be achieved by using powder processing equipment. This requires an automatic programming function that enhances the machine tool and a fixture and device for positioning the electrodes and the workpiece. The use of graphite electrode materials in the roughing of large workpieces is also a good way to improve the processing efficiency.
e. Informatization Information, matter and energy are the three elements of a manufacturing system. With the application of computer, automation and communication network technology red manufacturing systems, the role of information is becoming more and more important. The investment in information in the manufacturing process has become a major factor in determining product costs. The essence of the manufacturing process is the process of collecting, inputting, processing and processing various information resources in the manufacturing process. The final product can be regarded as the material expression of information, so information can be regarded as an industry, including in manufacturing. Among them. To this end, some enterprises have begun to use off-the-shelf production by using network technology, computer networking, information highways, and satellite transmission data. Distribute the production network to meet the needs of high-flexibility production in the 21st century.
f. Flexibility With the rapid development of science and technology and the continuous improvement of people's living standards, the speed of product upgrading is accelerating, which requires modern enterprises to have certain production flexibility to meet the changing needs of the market. The so-called flexibility refers to the ability of a manufacturing system to adapt to changes in various production conditions, which are related to system solutions, personnel and equipment. The flexibility of the system solution refers to the degree of freedom in processing different parts. Personnel flexibility refers to the ability of the operator to ensure the processing tasks, the amount of time and time required to adapt. Equipment flexibility means that the machine can adapt to the processing capabilities of new parts in a short period of time. There are many forms of flexible manufacturing automation, such as the agile manufacturing (AM) proposed by the United States, whose main line is highly flexible production. The Independent Manufacturing Island (AMI) proposed by Professor Zhang Wei from Shanghai Tongji University is also a highly flexible production model.
g. Integration The role of integration is to integrate multiple unit systems that were originally operating independently into a new system that works together and is more powerful. Integration is not a simple connection. It is achieved through unified planning and design, analysis of the roles and interrelationships of the original unit system and optimization and reorganization. The purpose of integration is to realize the functional integration of manufacturing enterprises. Functional integration requires technology integration through modern management technology, computer technology, automation technology and information technology, and also emphasizes human integration. Since there is no one in the system, the system runs. The effect and business management ideas, operating mechanism, and management model are all related to people. While integrating technology, we should also emphasize the integration of management and people. Integrated production will become the dominant production method for the 21st century.

Third, the application and development trend of ultra-precision machining Ultra-precision machining refers to sub-micron (size error is 0.3-0.03μm, surface roughness is Ra0.03 ~ 0.005μm) and nano-scale (accuracy error is 0.03μm, surface Processing with roughness less than Ra0.005μm). The process and technical measures taken to achieve these processes are called superfinishing techniques. Coupled with measurement technology, environmental protection and materials, people call this technology super-fine engineering. Ultra-precision machining mainly includes three fields: ultra-precision machining, such as ultra-precision cutting of diamond tools, and processing of various mirrors. It has successfully solved the processing of large parabolic mirrors for laser nuclear fusion systems and astronomical telescopes. Ultra-precision grinding and grinding processes such as coating surface processing of high-density hard disks and processing of large-scale integrated circuit substrates. Ultra-precision special processing such as large-scale integrated circuit chip graphics are processed by electron beam, ion beam etching, line width up to 0.1μm. If processed by scanning tunneling electron microscopy (STM), the line width can reach 2~5nm.

a. Ultra-precision cutting Ultra-precision cutting begins with SPDT technology, which is supported by air bearing spindles, pneumatic slides, high rigidity, high precision tools, feedback control and ambient temperature control to achieve nanometer surface roughness. It is widely used in diamond tool milling, and is widely used in copper planar and aspheric optical components, plexiglass, plastic products (such as camera plastic lenses, contact lens lenses, etc.), ceramics and composite materials processing. The future trend is to use coating technology to improve the wear of diamond tools in the process of hardening steel. In addition, the processing of tiny parts such as MEMS components requires small tools. At present, the size of small tools can reach 50-100 μm. However, if the processing geometry is sub-micron or even nano-scale, the tool diameter must be reduced again. Materials such as carbon nanotubes are used to make turning tools or milling cutters with ultra-small tool diameters.
b. Ultra-precision grinding Ultra-precision grinding is a mirror grinding method developed on the basis of general precision grinding. The key technology is the dressing of diamond grinding wheel, which makes the abrasive grain have micro-blade and contour. The processing objects for ultra-precision grinding are mainly brittle and hard metal materials, semiconductor materials, ceramics, glass, and the like. After grinding, the surface to be machined leaves a large number of extremely fine grinding marks, the residual height is extremely small, and the micro-blade sliding, rubbing and polishing effects can obtain a machined surface with high precision and low surface roughness. Precision grinding can produce cylindrical parts with a roundness of 0.01 μm, a dimensional accuracy of 0.1 μm and a surface roughness of Ra 0.005 μm.
c. Ultra-precision grinding Ultra-precision grinding includes mechanical grinding, chemical mechanical grinding, floating grinding, elastic emission processing and magnetic grinding. The key conditions for ultra-precision grinding are virtually vibration-free grinding motion, precise temperature control, a clean environment, and a small, uniform abrasive. The ultra-precision grinding process has a spherical surface of 0.025 μm and a surface roughness Ra of 0.003 μm.
d. Ultra-precision special processing Ultra-precision special processing mainly includes laser beam processing, electron beam processing, ion beam processing, micro-EDM processing, fine electrolytic processing and electrolytic grinding, ultrasonic electrolytic processing, ultrasonic electrolytic grinding, ultrasonic electric spark and other composite processing. . Laser and electron beam processing can achieve punching, precision cutting, forming and cutting, etching, lithography exposure, processing laser anti-counterfeiting marks; ion beam processing can achieve atomic and molecular level cutting; micro-discharge machining can achieve extremely fine Metal material removal, processing of fine axes, holes, slit planes and curved surfaces; fine electrolytic machining can achieve nanometer precision, and the surface does not produce machining stress, often used for mirror polishing, mirror thinning and some require stress-free processing. occasion.
The countries with leading edge in ultra-precision machining technology are the United States, the United Kingdom and Japan. The ultra-precision processing technology in these countries is not only high in overall set, but also highly commercialized. In the 1950s, the ultra-precision cutting technology of diamond tools was not developed, called "Single Point Dia-mond Turning" or "micro-inch technology" (1 micro-inch = 0.025 μm), and the corresponding air bearing was developed. The super-precision machine tool for the spindle is used to process laser nuclear fusion mirrors, tactical missiles and spherical and aspherical large parts for manned spacecraft. The Cranfield Institute of Precision Engineering (CUPE), affiliated to the Cranfield Institute of Technology, is a unique representative of the UK's ultra-precision machining technology. For example, Nanocentre (Nano Machining Center) produced by CUPE can perform ultra-precision turning, grinding heads and ultra-precision grinding. The shape of the workpiece can be up to 0.1μm and the surface roughness Ra<10 nm. Japan's research on ultra-precision processing technology started relatively late compared to the United States and Britain, but today the world's fastest-developing ultra-precision processing technology. Beijing Machine Tool Research Institute is one of the main units for ultra-precision machining technology research in China. It has developed a variety of different types of ultra-precision machine tools, components and related high-precision test instruments, such as precision bearings with a precision of 0.025μm, JCS. -027 ultra-precision lathe, JCS-031 ultra-precision milling machine, JCS-035 ultra-precision lathe, ultra-precision lathe CNC system, copier drum processing machine, infrared high-power laser mirror, ultra-precision vibration-displacement micrometer, etc. It has a leading domestic and international advanced level. Harbin Institute of Technology has conducted fruitful research in diamond ultra-precision cutting, diamond tool crystal orientation and sharpening, and diamond micro-powder grinding online repair technology. Tsinghua University has carried out in-depth research on integrated circuit ultra-precision processing equipment, disk processing and testing equipment, micro-displacement table, ultra-precision belt grinding and grinding, ultra-precision grinding of diamond micro-grinding wheel, and non-circular cross-section ultra-precision cutting. Research and the corresponding products are available. Compared with the US and Japan, China's ultra-precision processing technology still has a lot of gaps, especially in the super-finishing of large optical and non-metallic materials. The gap between ultra-finishing efficiency and automation technology is particularly obvious.

Ultra-precision machining will be developed in the direction of high precision, high efficiency, large-scale, miniaturization, intelligence, process integration, integration of online processing and inspection, and greening.
a. High precision and high efficiency.
With the continuous advancement of science and technology, the requirements for precision, efficiency and quality are getting higher and higher, and high precision and high efficiency have become the eternal theme of ultra-precision machining. Ultra-precision cutting and grinding technology can effectively improve machining efficiency. CMP and EEM technologies can guarantee machining accuracy, while semi-fixed abrasive processing methods and electrolytic magnetic grinding, magnetorheological abrasive flow processing and other composite processing methods can balance efficiency and precision. The processing method has become a trend of ultra-precision machining.
b. Large and miniaturized.
Due to the development of aerospace and other technologies, large-scale optoelectronic devices require large-scale ultra-precision processing equipment, such as the ultra-precision machining machine for large-scale optical devices with a diameter of 2.4 to 4 m developed by the United States. At the same time, with the development of micro-mechanical electronics, photoelectric information and other fields, ultra-precision processing technology to miniaturization, such as micro-sensors, micro-drive components and power devices, micro-aerospace devices, etc., require micro-super precision processing equipment.
c. Intelligent.
Reducing the dependence of processing results on artificial experience with intelligent equipment has always been the goal of the manufacturing field. The degree of intelligence of processing equipment is directly related to the stability of processing and processing efficiency, which is more obvious in ultra-precision machining.
d. Process integration.
Today's competition among enterprises tends to become hot, and high production efficiency is increasingly becoming a condition for enterprises to survive. In this context, there has been a call for “taking grinding and research” or even “selling with grinding”. On the other hand, the trend of using a single machine to perform a variety of machining operations (such as turning, drilling, milling, grinding, finishing) is becoming more and more obvious.
e. Integration of online processing and testing.
Due to the high precision of ultra-precision machining, it is necessary to develop integrated processing and inspection technology to ensure product quality and increase productivity. At the same time, due to the accuracy of the processing equipment itself, it is sometimes difficult to meet the requirements. The method of on-line detection, working condition monitoring and error compensation can improve the accuracy and ensure the processing quality.
f. Green.
Abrasive processing is the main means of ultra-precision machining. The manufacture of abrasives themselves, the consumption of abrasives in processing, the energy and materials consumed in processing, and the processing fluids used in processing are extremely burdensome on the environment. China is the largest country in the production and consumption of abrasives and abrasives. It has become a top priority for developed countries and Taiwan in China to strictly control the waste liquid, exhaust gas emissions and standards of semiconductor manufacturers. To this end, researchers from various countries have conducted research on the waste liquid and waste gas recovery treatment generated by CMP processing. The green ultra-precision machining technology improves the vitality of the environment while reducing the environmental burden.

4. Precision and ultra-precision machining development strategy Precision and ultra-precision machining have matured over the decades. Whether it is ultra-precision machine tools, diamond tools or ultra-precision machining processes, a complete set of ultra-precision manufacturing technology systems has been formed. In order to push the foundation of mechanical manufacturing to a higher level, it is now moving towards nanometer precision or nanometer precision, and its prospects are very encouraging. With the rapid development of science and technology and increasingly fierce market competition, more and more manufacturing industries have begun to invest a large amount of human, financial and material resources into the research and implementation strategies of advanced manufacturing technologies and advanced manufacturing models.

1. The use of integration and innovative ideas Precision and ultra-precision machining technology is an important means of developing science and technology. Therefore, it has received extensive attention from all countries in the world, so it has continuously obtained new results, but because its requirements are at the limit of precision. Traditional and single technologies are often difficult to break through. It is necessary to comprehensively use information technology to integrate and reorganize through integration and analysis to further meet higher requirements.
Precision Machining Technology is a systematic project that integrates the results of machine tools, tools, metrology, numerical control, materials, and environmental control. It is used in a comprehensive manner for different processing objects and different design requirements. Ultra-precision machining technology is also gradually developed under the conditions of various technical support, and at the same time, it is often enriched and improved by taking new achievements of various technologies. Ultra-precision machining technology is inseparable from innovation every step of the way, which is determined by the location of ultra-precision machining technology, because this technology is always at the forefront of development. The need for rapid development has determined that it must innovate.
2. Advanced Manufacturing Model Application Manufacturing model refers to the form and operation mode of enterprise system, operation, management, production organization and technical system.
a. Agile Manufacturing General Motors Corporation and Lehigh University introduced agile manufacturing (AM) in 1988. AM is prospering in an unpredictable and constantly changing competitive environment, with products and services that drive customer demand. Make a production model that responds quickly. The characteristics of AM are:
1 Inter-enterprise integration. Give full play to the strengths of each company and work together to achieve the goal of limiting the market.
2 has a high degree of manufacturing flexibility. Manufacturing flexibility refers to the rapid manufacturing of the manufacturer's requirements for rapid market conversion and the realization of multiple varieties of products.
3 Give full play to the role of people, continuously improve the quality and education level of enterprise employees, and optimize the distribution of human-computer functions.
b. Virtual Manufacturing Virtual Manufacturing (VM) is a new concept proposed internationally. VM is closely related to AM. The characteristics of the VM are: when new opportunities arise in the market, organize several related companies to reorganize and coordinate the work of different companies and factories in different locations. Before running, it is necessary to analyze whether the combination is optimal, whether it can be coordinated, and the benefits and risks after commissioning. This joint company is called a virtual company. The virtual company runs through a virtual manufacturing system. Therefore, research and development of virtual manufacturing technology (VMT) and virtual manufacturing system (VMS) is of great significance. The United States calls AM the manufacturing development strategy of the 21st century.
c. Integrated Manufacturing Dr. Harrington proposed the concept of Computer and Integrated Manufacturing (CIM) in the book Computer and Integrated Manufacturing. The core content of integrated manufacturing is: manufacturing companies from the market forecast, product design, processing and manufacturing, business management and after-sales service is an inseparable whole, need to be considered. The essence of the entire manufacturing process is the process of information collection, transmission and processing. The final product produced can be regarded as the material expression of information. Integration is the core of CIM. This integration is not only the integration of objects, but also the integration of technology and function integration characterized by information integration. The computer is an integrated tool. The computer and auxiliary unit technologies are the basis of integration, information exchange. It is a bridge, and information sharing is the key. The purpose of integration is to rationalize and optimize the organizational structure and operation mode of the enterprise, so as to improve the dynamic response speed of the industry to market changes, and pursue the highest overall efficiency and long-term benefits.
d. Intelligent Manufacturing Intelligent Manufacturing (IM) was first proposed in the US Publishing Research IM and IMS books. It is characterized by a highly flexible and highly integrated approach in all aspects of the manufacturing industry, through computer and simulation of intelligent activities of human experts for analysis, judgment, reasoning, conception and decision making, in order to replace or extend the people in the manufacturing environment. Part of the mental work, and the collection, storage, improvement, sharing, inheritance and development of human experts' manufacturing intelligence. The purpose of manufacturing intelligence is to model the skills of manufacturing workers and human expert knowledge through integrated knowledge engineering, manufacturing software systems, robot vision and robotic control, so that intelligent machines can be produced in small batches without human intervention.
e. Green manufacturing Green manufacturing is also known as environmentally conscious manufacturing and environmentally oriented manufacturing. That is, a modern manufacturing model that takes into account environmental impacts and resource consumption. The goal is to minimize waste and harmful emissions throughout the life cycle of design, manufacturing, packaging, transportation, use, and end-of-life disposal, with minimal negative impact on the environment, health-free, and highest resource utilization. The economic and social benefits of enterprises are higher.

Conclusion Precision and ultra-precision machining is one of the most important development directions of modern machinery manufacturing. It plays a vital role in improving the performance, quality and development of high-tech products, and has become a success in international competition. The key technology.我国的制造业发展已进入了高速发展阶段，中国民营企业已具备足够的经济实力来使企业迈向现代化，先进设备的引进和大量专业人才的涌入使许多沿海地区的制造业水平迅速提高。随着国家决策的科学化、民主化进程不断深入，相信我国的制造业会更快速、更健康地发展。

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