Requirement and Selection of Tool Materials in High Speed Ma
Category：News
PublishedDate：2017-09-15
In the development of machining industry, the tool has a direct impact on high precision, high flexibility, high efficiency and environmental awareness. Choose the right cutting tool plays a key role in the machining. High speed cutting of machining is the development direction of the cutting process and has become the main stream of cutting. Therefore, it is necessary to choose the right cutting tools in different machining condition.
1 The cutting conditions of Tool material in the high-speed cutting
1.1 Sufficient wear resistance and high hardness
Tool material should have a relatively high wear resistance, which can resist the tool wear that the workpiece produced. The hardness higher, The wear resistance better. Tool material contain wear-resistant alloy carbide more, the more fine the grain, the more uniform distribution, the wear resistance will be the corresponding better.
1.2 High strength and toughness
The tool must have a high strength and toughness, in order to prevent the cutting tools chipping and fragmentation, the tool need to withstand a variety of stress and impact in the cutting process. Tool materials need to choose the materials that have bending strength and impact toughness.
1.3 Good stability and heat resistance
The tool material needs to be able to withstand higher temperatures, good antioxidant properties and heat resistance. In particular, the better the heat resistance of the material, the higher the cutting speed that the material can allow, which is important to measure the performance of the tool material.
2 The type of tool material
The application and development of the High-speed cutting tool are: high-speed steel → carbide → ceramic → super-hard materials. Recently, enterprises and factories often use a lot of high-speed tool materials, but there are mainly diamond, cubic boron nitride (CBN), ceramics and metal ceramics that TiC(N) based carbide, different tool materials have different performance, has its specific scope of application, respectively, as follows.
2.1 Diamond
Diamond has two kinds of natural and man-made, they are carbon allotrope. The price of natural diamonds is particularly high and is not widely used, but man-made diamonds are made from graphite at very high temperatures, especially at high temperatures, and are particularly high in hardness, up to 10000HV. In non-metallic materials, non-ferrous metals and alloy process, diamond tool is very suitable. Diamond tools are widely used in automotive, aerospace, defense industry and other fields. Diamond tool is not suitable for processing iron material, the reason is that the diamond and iron have a strong chemical affinity, at high temperatures iron atoms easily interact with carbon atoms to convert it into graphite structure, the tool is very easy to damage. When the temperature reaches 800℃, the diamond tool in the air will carbonize and abruptly wear [3]. The Thermal stability of Diamond is relatively poor, it will lose its hardness, mainly used in ultra-precision areas.
2.2 Cubic boron nitride
Cubic boron nitride is a purely synthetic material, it is made by the hexagonal boron nitride in high temperature, high pressure conditions by adding catalyst. CBN is a dense phase of boron nitride, has high hardness, similar to the hardness of diamond, its heat resistance can reach 1300 to 1500 degrees Celsius, the higher the hardness will be able to change the advantages of the tool, and to a large extent So that a substantial increase in processing efficiency.
2.3 Ceramic cutting tools
Ceramic cutting tools have two main types: silicon nitride and alumina base, they are obtained by adding oxides, borides, nitrides, carbides and like in the silicon nitride matrix and alumina, respectively there are also multi-phase ceramics. Mainly used for processing wear-resistant cast iron and hardened steel alumina-based ceramics. Mainly used for finishing and semi-finishing high hardness materials, cast iron, steel, silicon nitride ceramic for continuous cutting.
High temperature strength, high temperature hardness, thermal conductivity, oxidation resistance and thermal shock resistance of TiC (N) -based carbide TiC (N) -based cemented carbide on the surface coating of the tool material are all improved and the affinity with steel is small, the friction coefficient is also small, anti-crescent-worn wear and anti-adhesive ability is strong, generally in the welding or indexing blade. Coated TiC (N) -based cemented carbide, that is, the friction coefficient of the cermet is small enough, the hardness is high enough, the resistance to wear is also strong enough, the chemical stability is good enough, because the coating enhances the oxidation and anti-stick Advantage, making the tool wear resistance significantly improved. Its cutting speed can be increased to the original 35 and 52, the tool life can be increased several times or even several times. For high-speed processing stainless steel, malleable cast iron and carbon steel, you can get the surface roughness reduction with coating carbide insert.
3 Conclusion
In recently years, with the continuous development of the markte, the cutting tools are improved, in current times, the main cutting tools materials in the world include ceramic cutting tools, coating carbide inserts, pcd inserts and cbn insert. And one of the famous manufacturer of superhard cutting tools (pcd and cbn inserts) is Halnn. With more than 10 years experience on superhard cutting tools, Halnn has researched many cbn inserts grade that have been widely used in the market, such as solid cbn insert BN-K1, BNK30, BN-S0 specific for gray cast iron parts, and BN-H21, BN-S20 specific for interrupt turning condition, also have some other grade for finish processing with good performance: BN-H10,BN-K10.
If you would like to know more about pcbn inserts or pcd tools, please feel free to contact with us info@halnntools.com, Whatsapp:+8615617635382