Surface quality limits for precision machining

According to the temperature state of the workpiece to be processed, it is divided into cold processing and hot processing. Generally processed at room temperature, and does not cause chemical or phase changes in the workpiece, called cold processing. Generally, processing at a state higher than or lower than normal temperature will cause chemical or phase changes in the workpiece, called hot processing. Cold processing can be divided into cutting processing and pressure processing according to the difference in processing methods.

Common hot work is heat treatment, forging, casting and welding. The former pursues the precision and surface quality limit of processing, and the latter includes the automation of product design, manufacturing and management, which is not only an important means to quickly respond to market demand, improve productivity and improve working conditions, but also an effective measure to ensure product quality, and the two are closely related.

Many precision and ultra-precision machining rely on automation technology to achieve the expected indicators, and many manufacturing automation depends on precision machining to achieve accurate and reliable. Both have a global and decisive role and are the pillars of technology. The use of precision machine tools and precision measuring tools and measuring instruments to achieve. Machining accuracy of 0.1 micron or more is called ultra-precision machining.

The surface micro-roughness (surface roughness average height difference) of the part is less than 0.1 micron. Some parts can also meet precise mechanical or other physical characteristics, such as the torsion stiffness of the float gyroscope torsion bar, the stiffness coefficient of the flexible element, etc. Rely on the accuracy of the guide rail and spindle of the machine tool to obtain high mutual position accuracy. High-speed milling with a carefully ground diamond head results in an accurate mirror. It is also related to the selection and balance of grinding wheel, the machining accuracy of the workpiece center hole and other factors. Fine grinding can obtain a dimensional accuracy of 1 micron and a non-roundness of 0.5 micron.