Manufacturing is an important pillar of the national economy of a country or region. The so-called advanced manufacturing technology is a production technology that integrates mechanical engineering technology, electronic information technology (including microelectronics, optoelectronics, computer software, hardware, modern communication technology), and automation technology, as well as material technology and modern management technology. The goal pursued by advanced manufacturing technology is to achieve high-quality, accurate, material-saving, energy-saving, clean, efficient, and flexible production to meet social needs.
Precise machining technology is an advanced manufacturing technology developed to meet the needs of modern high-tech and is the basis for the implementation of other high-tech. The development of precision machining technology has also promoted the development of machinery, hydraulics, electronics, semiconductors, optics, sensor and measurement technology, and materials science.
Usually, machining can be divided into three stages: general machining, precision machining, and ultra-precision machining by machining accuracy. At present, accurate machining refers to the machining technology with a machining accuracy of 1 to 0.1 microns and a surface roughness of Ra0.1 to 0.01 microns. But this limit is constantly changing with the advancement of machining technology, and today's accurate machining may be tomorrow's general machining. There are two problems should be solved by accurate machining. One is machining accuracy, including geometric tolerance, dimensional accuracy and surface condition. The second is processing efficiency. Some processing can achieve better processing accuracy, but it is difficult to achieve high processing efficiency.
The traditional precise machining methods include cloth wheel polishing, abrasive belt grinding, ultra-fine cutting, fine grinding, honing, grinding, ultra-fine grinding and polishing technology, magnetic particle finishing, etc.
1. Polishing. It is a kind of micro-machining on the surface of the workpiece by mechanical, chemical and electrochemical methods, which is mainly used to reduce the surface roughness of the workpiece. The commonly used methods of precise machining and polishing are manual or mechanical polishing, ultrasonic polishing, chemical polishing, electrochemical polishing and electrochemical-mechanical composite processing.
2. Belt grinding. It is to use the blended cloth with the abrasive to process the workpiece, which belongs to the category of coated abrasive grinding and has the characteristics of high productivity, good surface quality and wide application range. At present, great achievements have been made in abrasive belt materials and production processes. There are abrasive belt series suitable for different occasions. General and special abrasive belt grinding machines have been produced, and the degree of automation has been continuously improved.
3. Precision cutting. Cutting with high-precision machine tools and single crystal diamond tools is mainly used for accurate machining of soft metals such as copper and aluminum that are not suitable for grinding, and has good optical properties.