Chapter 5 - Measurement Technology in Precision Machining Courseware.ppt

I can't help you accordingly for this need. You can try to provide other topics and I will try my best to provide you with support and answers. 1, a technology called precision and ultra-precision machining technology, its main instructor is Li Songhua, there are 5.1 part of the precision measurement technology overview, 5.2 part of the measurement of the benchmark, 5.3 part of the straightness, flatness and perpendicularity of the measurements, 5.4 part of the Angle and the measurement of circular indexing, 5.5 part of the roundness and rotary accuracy of the measurements, 5.6 part of the laser measurement, 5.7 part of the free measurement of surfaces, and they are all in the precision category of Chapter 5.

2, processing in the measurement technology, precision processing in the measurement technology, section 1 1, the overview of precision measurement technology, precision measurement technology is the basis for the development of machinery industry, precision measurement technology is one of the prerequisites for the development of machinery industry. Precision measurement technology is the basis for the development of machinery industry, precision measurement technology is one of the prerequisites for the development of machinery industry. There are roles, there are micrometer class gauge reasons, there are micrometer class gauge reasons, there are micrometer comparator reasons, there are makes the processing accuracy to what extent, there are micrometer comparator reasons, there are makes the processing accuracy to what extent, there are roundness instrument and other precision measuring instruments reasons, there are roundness instrument and other precision measuring instruments reasons, there are makes the processing accuracy to what extent, there are laser interferometer Reasons, some make the processing accuracy to what extent, some micrometer class gauges, some make the processing accuracy of 0.01mm, some micrometer class gauges, some make the processing accuracy of 0.01mm, some micro comparator, some make the processing accuracy of 1m or so, some micro comparator, some make the processing accuracy of about 1m, some roundness instrument and other precision Measuring instruments, some make the processing accuracy of 0.1m, some laser interferometer, some make the processing accuracy of 0.01m. At present, exists in some areas of basic industry, precision measurement has become unable to be divided into separate and independent part of the existence of the present, is in some areas of basic industry.

3. Precision measurement has become an indispensable and extremely important component. In the electronics industry sector within this category, precision measurement technology has also been elevated to an unprecedented height. For example, the manufacture of ultra-large-scale integrated circuits, the current semiconductor process typical line width is 0.25m, towards 0.18m for the transition, the line width predicted in 2009 is 0.07m. In addition, in the lattice parameters of high-purity single crystal silicon. In addition, precision measurement techniques are required for lattice parameter measurements of high-purity single crystal silicon, for measurements of biological cells, for measurements of air pollution particles, for measurements of petroleum fibres, and for basic research on nanomaterials, without exception.

4. Precision testing is the necessary means for ultra-precision machining. The key technology mainly covers these: first, involving the precision measurement of geometric dimensions and measurement of the instrument used; second, including surface quality inspection technology and the corresponding measuring instruments; third, is the integration of measurement technology. High machining accuracy has to rely on high-precision measurement technology to ensure that high machining accuracy needs to be high-precision measurement technology to ensure that the measured accuracy is usually higher than the machining accuracy of an order of magnitude, there are high-precision detection methods, the detection of the displacement of dual-frequency laser interferometry, as well as the X-ray interferometer that the accuracy of up to 0.1 nm, the detection of machined surfaces have scanning tunnelling microscope, as well as the atomic force microscope.

5, atomic force microscope, its accuracy of up to 0.1nm, which belongs to the new development of precision measurement technology, precision measurement technology has a new development, extremely high precision detection methods and instruments in the development, such as scanning tunnelling microscope, as well as atomic force microscope. For precision online automatic measurement technology, it has real-time, dynamic, automatic characteristics, can be in one-dimensional space and three-dimensional space, especially any complex surface implementation of automatic measurement, and its measurement data automatic acquisition and processing technology is also developing, the technology covers the measurement of data acquisition, processing, display and printing and other aspects of this process with the help of microelectronics technology and computer technology can be realised. In addition, regarding the environmental conditions of precision measurement, only when the corresponding conditions are met can reliable measurement results be obtained.

In addition to precision measuring instruments and methods, there must be a suitable measuring environment, which is a necessary condition, and constant temperature condition is one of them, and its standard temperature is 20. Vibration isolation condition is also a necessary condition, in order to avoid the vibration and reduce the measurement error, and also consider the self-weight, air pressure, motion acceleration and other environment. For example: a 100mm long steel rod, when it is placed vertically and horizontally, the measurement of its length is not the same; when placed vertically, its length will be shortened by 0.002m. Another example: there is a 1m long steel rod, when it is in a vacuum and atmospheric environment for measurement, the measurement of its length is also different; in the measurement of the vacuum environment, its length will be bigger by 0.3m. gas Gas pressure changes, the object has acceleration, the length of the measured value will be different. Third, the selection of measuring instruments and gauge materials, first, according to the coefficient of thermal expansion of the material to be selected, second, according to the stability of the material and wear resistance to be selected. In the case of constant temperature measurement room, to select the linear expansion coefficient as small as possible; in the temperature fluctuation amplitude of the workshop, the selection of the gauge linear expansion coefficient should be as close as possible to the measured parts; zirconia ceramic.