Tungsten Carbide With High Material Properties

Posted by summer on March 24th, 2021

Tungsten carbide has high hardness and wear-resistance, The cutting speed of carbide tools is 4 to 7 times higher than that of high-speed steel with 5 to 80 times higher service life. Carbide products can cut hard materials of about 50HRC.

Cemented carbide is mainly micron-sized powders of carbides (WC, TiC) of high-hardness refractory metals. The main components are powder metallurgical products sintered in a vacuum furnace or a hydrogen reduction furnace with cobalt (Co), nickel (Ni), and molybdenum (Mo) as the binder.

The matrix of cemented carbide is composed of two parts: one part is the hardening phase and the other part is the bonding metal.

The hardened phase is the carbide such as tungsten carbide, titanium carbide, and tantalum carbide. Their hardness is very high, and their melting points are above 2000°C, and some even exceed 4000°C. The existence of the hardening phase determines the carbide has extremely high hardness and wear resistance.

Tungsten carbide WC grain size requirements for cemented carbide use different grain size WC according to different applications.

Carbide cutting tools

Carbide cutter is widely used for metal cutting and machining. Fine machining alloys such as foot cutter blades and V-CUT knives use ultra-fine, sub-fine, and fine-grained WC; rough-machining alloys use medium-grain WC; gravity cutting and heavy-duty cutting alloys use medium and coarse Granular WC as raw material.

carbide brazed tips

Carbide mining tools

The rock has high hardness and a large impact load. Coarse WC is adopted, and the rock impact is small with a small load. Medium-sized WC is used as raw material.

carbide mining tips

Carbide wear-resistant parts

When emphasizing its wear resistance, compression resistance and surface finish, adopt ultra-fine, sub-fine, fine, and medium-grain WC as raw material and use medium and coarse-grain WC raw materials as the main material for impact-resistant carbide wear parts.

tungsten carbide parts

The theoretical carbon content of WC is 6.128% (atomic 50%). When the carbon content of WC is greater than the theoretical carbon content, free carbon (WC+C) appears in the WC. The presence of free carbon causes the surrounding WC grains to grow during sintering, resulting in uneven grains of cemented carbide. Tungsten carbide parts generally require high combined carbon (≥6.07%), free carbon (≤0.05%), and total carbon is determined by the production process and scope of application of cemented carbide.

The bonding metal is generally iron group metals and cobalt and nickel are commonly used.