General Types of Cemented Carbides

Cemented carbide, often referred to as a hard compound carbide material, is a carbide composed of hard compounds of refractory metals and binding metals, produced through the powder metallurgy process. This material is highly versatile, suitable for various applications involving cutting, wear resistance, and impact resistance, making it widely used in everyday production. Let’s explore the different types of cemented carbide.
Cemented carbide boasts a range of excellent properties, including high hardness, wear resistance, superior strength and toughness, heat resistance, and corrosion resistance. Notably, its high hardness and wear resistance remain largely unchanged even at temperatures of 500°C, and it maintains high hardness at 1000°C. There are three primary categories of cemented carbide: cutting tools, geological and mining tools, and wear-resistant parts.
six categories of P, M, K, N, S and H

I. Cutting Tool Cemented Carbides

Cutting tool cemented carbides are categorized into six types based on their specific applications: P, M, K, N, S, and H.

– Class P: Composed of TiC and WC with Co (or Ni + Mo, Ni + Co) as the binder. These are typically used for machining long-chip materials like steel, cast steel, and malleable cast iron. For instance, grade P10 is well-suited for high-speed cutting operations such as turning, profiling, threading, and milling, especially under conditions with medium to small chip cross-sections.

– Class M: Based on WC with Co as the binder and a small amount of TiC. These are commonly used for machining materials like stainless steel, cast steel, manganese steel, and alloyed cast iron. Grade M01, for example, is ideal for high-speed, light-load, and vibration-free operations such as finish turning and boring.

– Class K: Composed of WC with Co as the binder and a small amount of TaC or NbC. These are used for short-chip materials like cast iron, cold-hard cast iron, and gray cast iron.

– Class N: Based on WC with Co as the binder and a small amount of TaC, NbC, or CrC. These are suitable for machining non-ferrous metals (e.g., aluminum, magnesium) and non-metallic materials (e.g., plastics, wood).

– Class S: Based on WC with Co as the binder and a small amount of TaC, NbC, or TiC. These are used for machining heat-resistant and high-alloy materials such as nickel-, cobalt-, and titanium-containing alloys.

– Class H: Composed of WC with Co as the binder and a small amount of TaC, NbC, or TiC. These are used for hard cutting operations, such as machining hardened steel and cold-hard cast iron.

II. Geological and Mining Tools

Cemented carbides for geological and mining tools are classified based on their application areas:

– A: Rock Drilling and Brazing Pieces: For example, grade GA05 is suitable for soft to medium-hard rocks with a uniaxial compressive strength below 60 MPa, while grades GA50/GA60 are for hard to very hard rocks with a uniaxial compressive strength above 200 MPa. As the grade number increases, abrasion resistance decreases while toughness improves.

– B: Geological Exploration Tools

– C: Coal Mining Tools

– D: Mining and Oil Field Drilling Tools

– E: Composite Sheet Matrix

– F: Snow Plow Blade

– W: Digging Teeth

– Z: Other Categories

These carbides typically have a Rockwell hardness of HRA 85 or higher and a bending strength of over 1800 MPa.

III. Wear-resistant Parts

Wear-resistant parts are categorized based on their application fields:

– S: Drawing Tools: Used for metal wire, bar, and tube drawing, such as drawing dies and sealing rings.

– T: Stamping Molds: Used for stamping operations, such as fastener and steel ball molds.

– Q: High-temperature and High-pressure Components: Used in high-temperature and high-pressure environments, such as synthetic diamond anvils and press cylinders.

– V: Rolling Mill Rolls: Used for wire rod rolling mills, such as rolls for high-speed wire rod rolling and finishing units.