What is Cemented Carbide – Cemented Carbide Properties, Types & Applications


When it comes to CNC cutting tools, cemented carbide is a very important material to know about. What is cemented carbide and what is it used for? Let’s take a look at its features, types, and typical uses.

What is Cemented Carbide Material?

Cemented carbide is a powder metallurgy alloy composed of one or more refractory carbide powders and metal powders (cobalt, nickel, etc.) used as an adhesive. It is generally used in the production of high-speed cutting tools and tools for cutting hard and abrasive materials, as well as cold-working molds, measurement instruments, and impact and vibration-resistant parts.

Features and Properties of Cemented Carbide

1) Excellent hardness and wear resistance

At normal temperatures, the hardness of cemented carbide can reach 8693HRA, which is equivalent to 6981HRC. It has a high hardness at 9001000 °C and great wear resistance. Cutting speed can be 4-7 times faster than with high-speed tool steel, service life can be 5-80 times longer, and hard materials with hardness up to 50HRC can be cut.

2) High strength and elasticity

Cemented carbide has a compressive strength of up to 6000MPa and an elastic modulus of (4-7) ×105MPa, which is greater than that of high-speed steel. However, its bending strength is modest, ranging from 1000 to 3000 MPa.

3) Excellent corrosion and oxidation resistance

It is resistant to air, acid, alkali, and other corrosion, and it is difficult to oxidize.

4) A low coefficient of linear expansion

During operation, the shape and dimensions remain stable.

5) No longer are formed items treated or reground.

Cutting or regrinding will not be performed after powder metallurgy forming and sintering because of the extreme hardness and brittleness of cemented carbide. Only EDM, wire cutting, electrolytic grinding, and other electric machining or specific grinding wheel grinding can be utilized when reworking is absolutely necessary. Specification products, often formed of cemented carbide, are brazed, bonded, or mechanically clamped to the cutter body or mold.

Common Types of Cemented Carbide

Common cemented carbide can be divided into three categories according to composition and performance characteristics: tungsten cobalt, tungsten titanium cobalt, and tungsten titanium tantalum (niobium). Tungsten cobalt and tungsten titanium cobalt cemented carbides are the most widely used in production.

1) Tungsten cobalt cemented carbide

The main components are tungsten carbide and cobalt, and the grade is indicated by the percentage of cobalt content after YG. For example, YG6 represents tungsten cobalt cemented carbide with a cobalt content of 6% and a tungsten carbide content of 94%.

2) Tungsten titanium cobalt cemented carbide

The main components are tungsten carbide, titanium carbide, and cobalt, and the grade is indicated by the percentage of titanium carbide content after the code YT. For example, YT15 represents tungsten titanium cobalt cemented carbide with 15% titanium carbide content.

3) Tungsten titanium tantalum (niobium) cemented carbide

This kind of cemented carbide is also called universal cemented carbide or universal cemented carbide. Its main components are tungsten carbide, titanium carbide), tantalum carbide or niobium carbide, and cobalt. The grade is indicated by the code YW followed by an ordinal number.

Application of Cemented Carbide

1) Cutting tool

Carbide is the most common material for cutting tools in CNC machining, including turning tools, milling cutters, planers, drills, etc. Tungsten cobalt cemented carbide is suitable for short chip processing of ferrous and non-ferrous metals and processing of non-metallic materials, such as cast iron, cast brass, bakelite, etc. Tungsten titanium cobalt cemented carbides are suitable for machining long chips of ferrous metals such as steel. Among similar alloys, those with more cobalt content are suitable for rough machining, while those with less cobalt content are suitable for finish machining. The service life of general cemented carbide for stainless steel and other difficult-to-machine materials is much longer than that of other cemented carbides.

2) Mold 

Cemented carbide is mainly used as cold drawing dies, cold punching dies, cold extrusion dies, cold pier dies, and other cold working die.

3) Measuring tools and wear-resistant parts

Cemented carbide is used for wearing surface inlay and parts of measuring tools, the precision bearing of grinder, guide plate and guide rod of centerless grinder, lathe center, and other wear-resistant parts.