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Traditional machining methods (general machining) are the same as precision and ultra precision machining methods. With the adoption of new technology, new technology, new equipment and new testing technology and instruments, the machining accuracy is constantly improving.

The continuous improvement of machining accuracy reflects the development trend of the level of material segmentation from the macro into the micro world. As time goes on, the machining accuracy which is considered difficult to achieve will become relatively easy. Therefore, ordinary processing, precision machining and ultra precision machining are only a relative concept, and the boundaries between them vary with time. The typical example of precision cutting and ultra precision machining is diamond cutting.

Diamond cutting is taken as an example. The radius of the knife edge has been developing in a smaller direction. Because its size directly affects the roughness of the machined surface, it is directly related to the reflectivity of the optical mirror, and the requirement for the reflectivity of the equipment is getting higher and higher. If the reflectivity of the laser gyroscope reflector has been raised to 99.99%, this will inevitably require diamond tools to be sharper. In order to carry out the thinning test, the target is to achieve chip thickness of nm, and the radius of the tool edge should approach 2.4nm. In order to achieve this height, the diamond grinder has changed the traditional structure. The spindle bearing adopts the air bearing as the support, the end face of the grinding disc can be corrected by the machine itself, so that the end face of the grinding disc is controlled by 0.5μ m below.

In terms of cutting tools, diamond grinding wheel is used to control the amount of feed and feed on the back. In ultra precision grinding machine, ductile grinding can be carried out, namely nano grinding. Optical surfaces can be obtained even on the surface of glass. 2 the development trend of precision processing and ultra precision processing is from the viewpoint of long-term development. Manufacturing technology is the main direction and strategic decision of developing national economy in all countries. It is one of the important means of national economic development. At the same time, it is a country's independent, prosperous and sustained economic development. A long - term plan to keep the lead in technology. The development of science and technology has also put forward higher requirements for precision machining and ultra precision machining technology. From large to celestial telescope lens, small to large scale integrated circuit line width μ m requirements for micro and micromechanical micro and nano size parts, regardless of size, the maximum size accuracy is close to nanometer; the shape of parts is increasingly complex, various aspheric is the current very typical geometric shape. Micromechanical technology brings a new trend for ultra precision manufacturing technology. Its micro degree makes the traditional manufacturing technology face a new challenge, promotes the improvement of the technical performance of various products. The development process presents a spiral circular development, and contributes directly to the progress of science and technology and human civilization. With the pursuit of high quality, miniaturization, high reliability and high performance, the ultra precision machining technology has been developed rapidly, and it has become an important part of modern manufacturing industry.