Metal Cutting Tools Materials--Superhard Cutting Tool Materials

Superhard cemented carbide cutting tool materials refer to diamond and cubic boron nitride. It should be noted that the processing of general materials or heavy use of high-speed steel and cemented carbide. Only high hardness or super finishing superhard cemented carbide cutting tool has a better economic efficiency.

The diamond (one of superhard cemented carbide cutting tool materials) is the hardest material found in nature, the two points natural diamond and synthetic diamond micro hardness 10000HV.

-There are three types of diamond tool (one of superhard cemented carbide cutting tool):

1. Natural single crystal diamond tool: natural single crystal diamond particles more than 100mg (0.5 carats), expensive, and its crystal structure of the diamond tool performance impact, mainly used for precision machining of non-ferrous materials and non-metallic. Single crystal diamond tool crystalline interface has a certain direction, different crystal surface hardness and wear resistance are large differences in the selection of a plane when sharpening, otherwise affect the quality of sharpening diamond tool.

2. Synthetic polycrystalline diamond tool: alloy catalyst role by graphite under high temperature and pressure transformed from. Synthetic polycrystalline diamond synthetic diamond microcrystalline under high temperature and pressure sintering can be made into the desired shape and size, inlaid arbor. Improve the impact strength, the diamond cutter larger choice of cutting parameters. The polycrystalline diamond crystallization interface no fixed direction, freely sharpening.

3. The diamond sintered body: The sintered cemented carbide substrate layer of about 0.5mm thick polycrystalline diamond. Diamond burn sintered body better strength, allows the cutting cross-section larger, can also be interrupted cutting, Therefore, this diamond tool may be used repeatedly regrinding.

The main advantages of diamond tool:

1) High hardness and wear resistance of diamond tools.

2) The diamond tool has good thermal conductivity, low thermal expansion coefficient. Therefore, the diamond tool cutting does not produce a great thermal deformation of the precision machining beneficial.

3) Diamond cutter blade surface roughness, the cutting edge is very sharp. Therefore, it is capable of a thin layer cutting, for ultra-precision machining.

Polycrystalline diamonds is used for manufacturing sharpening cemented carbide cutting tool for grinding wheels, cutting blade and grinding wheel with marble and other stone products. The diamond tool is mainly used for the non-ferrous materials, such as the finishing of the Al-Si alloy, super finishing; high hardness of the non-metallic material, such as compression of the finishing of wood, ceramic, corundum, glass, etc.; and difficult to process composite materials processing . The diamond heat resistance temperature of only 700 to 800 ° C, its working temperature is not too high, diamond and easily with carbon affinity, it is not appropriate processing carbon black metal.

Superhard cemented carbide cutting tool materials - cubic boron nitride (CBN)

CBN is one of superhard cemented carbide cutting tool materials, transformed from hexagonal boron nitride (white graphite) under high temperature and pressure, the 1970s developed a new type of superhard cemented carbide cutting tool material.

The main advantages of CBN tools (one of superhard cemented carbide cutting tools):

1) CBN tools are second only to diamond tools with high hardness and wear resistance of 3500-4500HV,.

2) CBN tools have high thermal stability, 1300 ℃ oxidation does not occur with most metals, the iron-based material is not from a chemical action. So, they can cut high hardness steel material and heat-resistant alloy with high speed. these superhard cemented carbide cutting tool bond and diffusion wear are small.

3) CBN tools have a better thermal conductivity; such superhard cemented carbide cutting tool and steel friction coefficient are small.

4) CBN flexural strength and fracture toughness of the range between the ceramic and cemented carbide.

Because a series of advantages of the CBN materials, such superhard cemented carbide cutting tool for roughing and semi-finishing of hardened steel, chilled cast iron. Can speed cutting high temperature alloys, thermal spray materials difficult to machine materials.

CBN and cemented carbide can also be sintered into one, such a CBN sintered body, the flexural strength of up to 1.47GPa, can be used after repeated regrinding.

Chinatungsten Online can provide various sizes and grades of diamond tool and other superhard cutting tool , non-standard products are also customized according to customer requirements. Welcome to consult and purchase [email protected], [email protected] .