At present, there are still many people in the machinery industry who do not know enough about the performance of PCD tools when applying them, and often cannot determine which industries or fields PCD tools are used for. Let's learn about the performance advantages and structural forms of PCD tools.
Ⅰ. Introduction of diamond PCD tools
As a superhard tool material, diamond has been widely used in cutting processing. The high price of natural diamond limits the development of diamond tools. In the 1970s, polycrystalline diamond (PCD) was synthesized by high-pressure synthesis technology, which solved the problem of the number of natural diamonds. The problem of rarity and high price has expanded the application scope of diamond tools to aviation, aerospace, automobile, electronics, stone and other fields.
Polycrystalline diamond (PCD) tools are mainly used for processing non-ferrous metals and other non-ferrous metals. They can sharpen sharp edges and obtain better machined surfaces. They are also the first choice for processing new non-metallic materials. They can cut hard High hardness products such as alloys and industrial ceramics.
Ⅱ. The performance advantages of PCD tools
1. The hardness of PCD can reach 8000HV, which is 80~120 times that of cemented carbide, and the wear resistance of PCD is better.
2. The thermal conductivity of PCD is 700W/MK, which is 1.5 to 9 times that of cemented carbide, even higher than that of PCBN and copper. Therefore, the heat transfer of PCD tools is rapid, and good heat transfer can extend the tool life to a large extent.
3. The friction coefficient of PCD is generally only 0.1 to 0.3, while the friction coefficient of cemented carbide is 0.4 to 1. Therefore, PCD tools can significantly reduce cutting forces, thereby extending tool life.
4. The thermal expansion coefficient of PCD is small, so the thermal deformation of the PCD tool is small and the machining accuracy is high. The greater the thermal deformation of the tool, the worse the surface quality of the processed workpiece. In order to process a workpiece with good surface quality, the thermal deformation of the tool must be strictly controlled.
5. The PCD tool has a small affinity with non-ferrous and non-metallic materials, and the tool tip is not easy to form a built-up edge during processing. The affinity between the tool and the material to be processed is small, so the material to be processed is not easy to adhere to the surface of the tool during processing, and it is not easy to form a built-up edge.
6. The PCD tool has a large elastic modulus and high breaking strength (three times higher than that of alumina), and the blunt circle radius of the cutting edge can be ground to a very small value, which is not easy to break, and can maintain the sharpness of the cutting edge for a long time.
Ⅲ. The structure of PCD tool
Polycrystalline diamond (PCD) tools are tools made by welding a PCD compact to a carbide or steel body. Since the PCD compact combines the high hardness, wear resistance, low friction coefficient and strength of single crystal diamond with the high flexural strength of tungsten carbide, the tungsten carbide layer of the compact provides the diamond layer with Mechanical support increases its flexural strength, while the cemented carbide layer is easy to weld, making it easy to make finished knives.
The structural forms of PCD cutters are: PCD inserts, PCD milling cutters, PCD reamers, PCD drill bits, PCD grooving cutters, and non-standard PCD cutters.
In a word, the PCD tool market continues to expand with the development of tool technology, and the application of PCD tools has further promoted the research on its design and manufacturing technology. Many well-known universities and tool manufacturers in China are actively carrying out research, development and production in this area.
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