Mar 05, 2020
1. Progress of ultra-precision machining and research
Precision machining is the core goal of industry and the core content of the country's scientific and technological capabilities. Ultra-precision machining technology under the background of automation has always been the focus and focus of technical processing. In CNC ultra-precision machining, it mainly includes software and hardware research, the latter research is more in-depth. In the hardware research system, the precision control of ultra-precision machining is an obstacle to diversification and specific control. The article aims at numerical control ultra-precision machining as the main content of the study, and involves future technological breakthroughs in machining accuracy, providing a theoretical and practical basis for subsequent practice and scientific research.
2. Ultra-precision machining requirements and affecting factors
During the ultra-precision turning process
Ultra-precision cutting refers to turning technology that uses ultra-hard materials such as diamond as turning tools. The surface roughness Ra can reach tens of nanometers. At this processing stage, the interaction between the accuracy of mechanical control and the choice of materials has a significant effect on the processing results.
During precision grinding
Using a fine-grained and plagiarized consolidated abrasive wheel and a high-performance grinder, the processing fineness is increased to more than 0.1nm, and the material of the grinder is taken out to achieve the processing surface roughness. The index coefficient has reached the mechanical structure. Maximum machining accuracy. Different precision control modes are different from the processing precision and surface roughness. The precision range produced is different. The accuracy obtained by sorting ranges from 12nm to 30nm. The best precision can reach the atomic level. More stable, the most accurate grinding method has a stability performance from 24 to 30, which varies greatly.
During the ultra-precise polishing process
Ultra-precision polishing is the use of mechanical and chemical action of fine abrasive particles, with the aid of soft polishing tools or chemical fluids, electric / magnetic fields, etc., in order to obtain a smooth or ultra-smooth surface, reducing or completely eliminating the process deterioration layer, thereby obtaining High surface quality processing methods.
3． Control and comparison of ultra-precision machining accuracy
In order to achieve the precision required by the industry, in addition to ensuring the stability and precision of the equipment, it is also necessary to ensure that the properties of the material can reach the level of processing at the atomic level. For the stability of ultra-precision processing and the directionality of the industry, diversified Ultra-precision machining methods have been selected, a variety of CNC ultra-precision machining methods and methods, and various machining accuracy studies have been performed for different industrial purposes. Processing stability and accuracy are important evaluation criteria for precision control ladders. The data analysis of the multi-parallel index evaluation system is carried out in different processing methods, which provides a reliable expression for the specific process selection. As the mean of the positive weight coefficients, it provides weight indicators for the total number of indicators.
4． Application of CNC Precision Control System Improvement Scheme
To improve machining accuracy and reduce the instability factors of CNC precision control, the first is to consider the vibration factors of the operation, and perform high-speed cutting and machining of precision boring. Under the premise that the speed is not less than 3000 rpm, the rotation speed of the precision electric spindle will be Acceleration, slight vibration may affect the surface roughness of the hole. In addition, for the improvement of the screw drive, the stability of the screw operation must be considered. The machining accuracy of the parts and the assembly accuracy of the boring machine must be high to meet the precision requirements of the screw drive. The operation must accurately grasp the height of the seat of the screw nut, to ensure the smoothness of the screw system, and to prevent the sliding table from running due to vibration. stable. The transformation eliminates the over-positioning situation of the screw drive, optimizes the structure, and makes adjustment easier and more convenient.
In summary, according to the distribution of machining accuracy and the influence nodes of the shape, after different classification and summary of different sections and methods, the accuracy characteristics of pattern processing combined with TOPSIS model were used to evaluate the quality of aspheric grinding control. Practical value. In the subsequent practice and feasibility study, we should continue to make technical breakthroughs to relevant systems through research to provide theoretical foundation and practical guidance for future processes.