The materials used to make the tool must have high hardness and wear resistance at high temperatures, necessary bending strength, impact toughness and chemical inertness, good processability (cutting, forging, heat treatment, etc.), and are not easily deformed.

       Usually when the material hardness is high, the abrasion resistance is also high; when the bending strength is high, the impact toughness is also high. However, the higher the material hardness, the lower its flexural strength and impact toughness. High-speed steel has high bending strength and impact toughness, and good machinability. Modern is still the most widely used tool material, followed by hard alloys.

        Polycrystalline cubic boron nitride is suitable for cutting high hardness hardened steel and hard cast iron, etc. Polycrystalline diamond is suitable for cutting non-ferrous metals, alloys, plastics and FRP, etc. Carbon tool steel and alloy tool steel are only used as Tools such as files, dies and taps.

        Cemented carbide indexable inserts have been coated with titanium carbide, titanium nitride, hard aluminum oxide, or hard composite layers by chemical vapor deposition. The physical vapor deposition method being developed can be used not only for carbide tools but also for high-speed steel tools such as drills, hobs, taps, and milling cutters. The hard coating acts as a barrier against chemical diffusion and heat conduction, slows down the wear of the tool during cutting, and increases the life of the coated insert by approximately one to three times over that of the uncoated one.

        Due to the high temperature, high pressure, high speed, and parts working in corrosive fluid media, more and more difficult-to-machine materials are applied, and the automation level of cutting and the requirements for processing accuracy are getting higher and higher. In order to adapt to this situation, the development direction of the tool will be to develop and apply new tool materials; to further develop the tool's vapor deposition coating technology, to deposit a higher hardness coating on a high-toughness, high-strength substrate to better solve The contradiction between the hardness and strength of the tool material; the development of the structure of the indexable tool; the improvement of the tool's manufacturing precision, the reduction of the difference in product quality, and the optimization of the use of the tool.

       Tool materials are roughly classified into the following categories: high-speed steels, hard alloys, cermets, ceramics, polycrystalline cubic boron nitride, and polycrystalline diamond.

        I mainly mention ceramics, ceramics used in cutting tools than carbide, but due to its brittle, the development is very slow. However, since the 1970s, the development has been relatively fast. There are two major ceramic cutting tool materials, namely alumina and silicon nitride. Ceramics as a cutting tool have the advantages of low cost, high hardness, good high temperature resistance, and have good prospects. Domestic and foreign products vary greatly. Tools are high-tech consumer goods!

        General machining centers are commonly used in the following materials: carbon tool steel, alloy tool steel, high speed steel, carbide, superhard materials.

Carbon tool steel

        Carbon tool steel refers to high-quality high-carbon steel with a carbon content of 0.65%-1.35%. The grades used as tools are generally T10A and T12A, and the room temperature hardness is 60-64HRC. When the cutting edge heats up to 200-250 degrees, its hardness and wear resistance will rapidly drop, thus losing the cutting performance.

Alloy tool steel

        In order to improve the performance of carbon tool steels, alloy elements such as manganese, chromium, tungsten, silicon and vanadium are often added to them to form alloy tool steels. The commonly used grades are 9sicr, GCr15, CrWMn and others. Compared with carbon tool steels, alloy tool steels have similar hardness after heat treatment, slightly higher heat resistance and wear resistance, and better heat treatment properties. However, compared with high-speed steel, the cutting speed and service life of alloy tool steel are far inferior to those of high-speed steel, making its application very limited. Therefore, alloy tool steels are generally only used to replace carbon tool steels.

 

High speed steel

       High-speed steel is a high-alloy tool steel containing tungsten, aluminum, chromium, vanadium and other alloying elements. The main advantages of HSS are its high hardness, strength and wear resistance, as well as its good heat resistance and quenchability. Its allowable cutting speed is more than twice that of carbon tool steels and alloy tool steels. After high-speed steel grinding sharp cutting edge, it is also known as front steel and white steel. High-speed steel is a kind of tool material with good comprehensive performance and wide application range. It is commonly used to manufacture complex-structured tools such as turning tools, milling cutters, drills, and reamers. Broaches, gear cutters, etc.

 

Carbide

       Cemented carbide is an alloy material produced by the powder metallurgy method. It is made of high hardness, high melting point metal carbides such as WC and TiC, and sintered with a metal binder such as cobalt at a high temperature.

       Carbide hardness is higher, at room temperature up to 89-93HRA, wear resistance and heat resistance are higher than the tool steel, 800-1000 degrees can still be normal cutting, the cutting speed is several times that of high-speed steel, The tool life is also increased by several dozen times, and it can process high-speed steel cutting tools difficult to cut materials, so it is widely used. However, it also has the disadvantages that the bending strength and impact toughness are lower than high-speed steels, and the cutting edge cannot be as sharp as high-speed steel cutters.

 

Superhard material

        The superhard materials are mainly made of adobe stone, standing mats of boron nitride and ceramics. Diamond is the hardest material in nature and its hardness can reach 10000 HV. Natural diamonds are expensive. rarely use. Synthetic diamond is made of graphite and sintered at high temperature. Mainly used for high-speed precision turning, boring non-ferrous metals and their alloys and non-metallic materials. When cutting copper alloy or aluminum alloy, the cutting speed can reach 800-3800M/MIN. Due to the high wear resistance of diamond, the processing dimensions and tool life are long. So often used in CNC machine tools, machine tools and automatic machine tools, the roughness after processing up to 0.1-0.025um. However, diamond tools, poor heat resistance, cutting temperature should not exceed 700-800 degrees. Low-intensity, brittle, and sensitive to vibration, only micro-cutting is recommended.

        The development of the tool occupies an important position in the history of human progress. The tool is a tool used for cutting machining in machinery manufacturing. China is the world's most promising tool market. Many multinational tool groups have made expanding their tool sales in China the top choice in their own development strategies. R&D centers, training centers, and logistics centers have all settled in China, radiating Asia with China as the center, and serving customers more directly and conveniently to better meet the needs of customers in the Asia Pacific region.