There are many methods for metal processing, and cutting is the most common and widely used metal processing. The use of cutting fluid plays an important role in metal cutting. During the metal cutting process, the friction between the tool and the workpiece, the tool and the chip creates a large friction, which increases the cutting force, the cutting heat and the deformation of the workpiece, which causes the tool to wear and also affects the quality of the machined surface. The role of cutting fluid is mainly reflected in the following four aspects: First, the cutting fluid has a cooling effect Due to the self-cooling ability of the cutting fluid, its direct cooling can not only reduce the cutting temperature, reduce tool wear, extend tool life, but also prevent workpieces. Thermal expansion, the effect of warpage on the machining accuracy, and the cooling of the machined surface inhibit the generation of the hot metamorphic layer. Second, the cutting fluid has a lubricating effect The lubricating effect of the cutting fluid means that it reduces the friction, wear and fusion and adhesion between the rake face and the chip, the flank face and the workpiece surface. Under certain conditions, the use of good cutting fluid can reduce the friction before and after the tool, thus reducing power, increasing tool life and obtaining better surface quality. More importantly, it reduces the chance of producing built-up edge tumors (ie, knife tumors). Third, the cutting fluid has a cleaning effect. During the cutting process, finely-cut chips, metal powder and grinding wheel sand powder (very much when machining cast iron, honing and fine grinding) are adhered to the tool, the two-piece machining surface and the moving parts of the machine tool. Between, resulting in mechanical scratches and wear, resulting in deterioration of the surface quality of the workpiece, tool life and machine accuracy. Therefore, the cutting fluid is required to have a good cleaning effect, and a certain pressure is often given during use to improve the flushing ability, and the finely divided chips, sand particles, and binder powder are washed away in time. Fourth, the cutting fluid has anti-rust effect During the machining process, the workpiece and the machine tool are rusted by the surrounding medium such as moisture, oxygen, sweat, acid and dust in the air. This rust is particularly prominent in high temperature, high humidity seasons or wet areas. At the same time, according to the current situation of long processing time of metal parts processed in China, the cutting fluid itself must not only cause rust on machine tools, tools and workpieces, but also have good anti-rust properties for metal products. The good overall properties of the cutting fluid make it play a huge role in metal cutting. Reasonable selection of cutting fluid can prolong tool life, ensure and improve the accuracy of machining, prevent corrosion and rust of workpieces and machine tools, improve cutting efficiency, reduce energy consumption and production costs. Http://news.chinawj.com.cn