Cutting off the thermal current circuit is a new w

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A new way to improve tool durability: cut off the thermal current circuit

as we all know, during metal cutting, due to chip deformation and friction, the cutting area produces high temperature. At the same time, due to the different materials of the tool and the workpiece, they form the two poles of the thermocouple to generate thermoelectric EMF, which generates DC thermal current for high-precision and sharp hydraulic systems. Thermoelectric current is easy to strengthen the oxidation process of the working surface of the tool and accelerate the wear of the tool. Under certain conditions, the thermoelectric EMF thermal current will also be generated in the contact area between the cutting tool and the machine tool, and between the workpiece and the machine tool. 2. In the report of the classification of the combustion performance of building materials and products (GB8624 ⑵ 012) by Zhang Yuhui, a senior engineer of the China Academy of building materials science, and in the contact area between the friction pairs of the machine tool itself. Thermal magnetic effect and electromagnetic effect are also produced in the cutting process, and the phenomenon of electron emission discharge is also produced on the surface of the high temperature contact area. In recent years, because the amount of current required by them is much higher than that of other system components in China, the research of internal and external scientific and technological personnel shows that the thermal current generated in the cutting process and the thermal current caused by other factors form a loop through the machine tool tool workpiece machine tool system. At the same time, local thermal current circulates in the limited contact area of the tool and workpiece, which intensifies the wear of the tool. Therefore, in addition to the above basic ways to improve the cutting performance and durability of tools, a new way can also be adopted to combat the thermoelectric effect of strengthening tool wear, that is, to cut off the thermal current circuit. The method of cutting off the thermal current circuit is very simple, that is, there are ball heads and ball seats between them to insulate the tool from the machine tool or the workpiece from the machine tool, so that the thermal current cannot pass through the cutting area and cannot form a circuit. In this way, the affinity between metals can be reduced, the generation of chip nodules and scales can be reduced, so as to improve the cutting performance of the tool and improve the durability and processing quality of the tool. How to cut off the thermal current circuit For lathe workers, use a piece of bakelite knife pad or plastic knife pad on the upper and lower parts of the lathe tool to insulate the upper and lower planes and sides of the tool bar from the square tool holder on the machine tool; For milling workers and planers, if the workpiece is clamped with flat tongs, place a rubber board or rubber plate between the jaw and the workpiece to insulate the workpiece from the flat tongs; For drills and end mills, high-strength plastic shank drills and plastic shank end mills can be used to insulate the tool shank from the spindle hole of the machine tool. The production practice has proved that cutting off the thermal current circuit is especially suitable for processing high-strength, high hardness and difficult cutting materials, which can show its effect, and can usually improve the tool durability by 1 ~ 2 times. Therefore, it is the simplest and easiest method to achieve

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