What role do cemented carbide cutting tools play in modern mechanical processing?

In the field of metal processing, cutting tools are key tools for efficient and precise processing. As a high-performance tool material, cemented carbide cutting tools are widely used in various cutting processes with their advantages of high hardness, high strength, good wear resistance and thermal stability, which greatly improves the processing efficiency and quality and promotes the development of the machinery manufacturing industry. A deep understanding of cemented carbide cutting tools will help us better grasp the key technologies of mechanical processing and promote the manufacturing industry to a higher level.

1. Definition and composition of cemented carbide cutting tools

Cemented carbide cutting tools are tools made of high-hardness and high-melting-point metal carbides (such as tungsten carbide, titanium carbide, etc.) and metal binders (such as cobalt, nickel, etc.) through powder metallurgy.

Among them, metal carbides are the main components of cemented carbide, which give the tool high hardness and wear resistance; the metal binder bonds the carbide particles together, giving the tool a certain strength and toughness. The two complement each other, allowing cemented carbide cutting tools to work stably under complex cutting conditions.

In addition, by adjusting the type and content of carbides and the content of binders, cemented carbides with different properties can be obtained to meet the needs of various cutting processes.

2. Characteristics of cemented carbide cutting tools

(1) High hardness and wear resistance

The hardness of cemented carbide cutting tools can usually reach HRA89-93, which is much higher than that of high-speed steel tools. During long-term cutting, its cutting edge can remain sharp and effectively reduce wear. For example, when processing alloy steel with higher hardness, the service life of cemented carbide tools is several times that of high-speed steel tools, which greatly reduces the frequency of tool replacement and processing costs.

(2) Good thermal stability

During the cutting process, the friction between the tool and the workpiece will generate a lot of heat, causing the tool temperature to rise sharply. Cemented carbide cutting tools have excellent thermal stability and can maintain good hardness and cutting performance in a high temperature environment of 800-1000℃, ensuring that the processing accuracy is not affected by high temperature and meeting the requirements of advanced processing technologies such as high-speed cutting.

(3) High strength and toughness

Although cemented carbide has high hardness, it can have certain strength and toughness by reasonably adjusting its composition and manufacturing process. Its bending strength can reach 1500-5000MPa, and its fracture toughness can reach 5-15MPa・m1/2. It is not easy to break or fracture when subjected to cutting force impact and vibration, and can adapt to a variety of complex cutting conditions.

(4) Good chemical stability

Cemented carbide is not easy to react chemically with the metal material being processed, which effectively reduces the adhesion and diffusion wear between the tool and the workpiece. This feature ensures that the tool can maintain stable cutting performance and obtain good processing surface quality when processing different materials.

3. What metal materials are suitable for cemented carbide cutting tools to process?

(1) Alloy steel

Alloy steel has high strength and hardness due to the addition of multiple alloy elements, and is more difficult to process. With high hardness and wear resistance, cemented carbide cutting tools can smoothly cut alloy steel. Whether it is low-alloy structural steel or high-alloy tool steel, it can achieve efficient processing and ensure processing accuracy and surface quality.

Carbide cutting tool display

(2) Stainless steel

Stainless steel has processing difficulties such as high toughness, high cutting temperature, and easy sticking to the tool. The chemical stability of cemented carbide enables it to effectively avoid sticking when processing stainless steel. Its good thermal stability can also cope with the high temperature generated during the processing, ensuring the normal operation of the tool and improving the processing efficiency.

(3) Cast iron

Cast iron has a high hardness and contains graphite and other structures inside, which causes greater wear on the tool. The high hardness and wear resistance of cemented carbide cutting tools make it an ideal choice for processing cast iron. It can quickly remove materials while ensuring the smoothness and dimensional accuracy of the processed surface.

(4) Non-ferrous metals

Although non-ferrous metals such as aluminum alloys and copper alloys have relatively low hardness, they have high requirements for the surface quality of the processed surface. The sharp cutting edge and stable performance of cemented carbide cutting tools can achieve precision processing of non-ferrous metals and meet their surface quality requirements.

4. Comparison of performance factors of cutting tools for different materials

Tool Material	Hardness	Wear Resistance	Heat Resistance
Cemented Carbide	HRA89 - 93, much higher than high-speed steel	High, able to maintain sharpness during long-term cutting	Can maintain good performance at high temperatures of 800 - 1000°C
High-speed Steel	HRA82 - 87	Good, but not as good as cemented carbide	General, the performance begins to decline at around 550 - 650°C
Ceramic Tool	Very high hardness, up to HRA91 - 95	High, excellent wear resistance	Good heat resistance, can work at high temperatures above 1200°C
Superhard Tool	The hardness of polycrystalline diamond (PCD) tool can reach above 10000HV, and the hardness of cubic boron nitride (CBN) tool can reach 8000 - 9000HV	Extremely high, one of the tool materials with the best wear resistance	The heat resistance of PCD tool is general, and graphitization will occur at 700 - 800°C. The heat resistance of CBN tool can reach 1400 - 1500°C

Tool Material	Strength and Toughness	Cutting Speed	Machined Materials	Manufacturing Cost
Cemented Carbide	Bending strength of 1500 - 5000MPa, fracture toughness of 5 - 15MPa·m1/2, with certain strength and toughness	Relatively high, much higher than high-speed steel tools	A variety of metallic materials such as alloy steel, stainless steel, cast iron, and non-ferrous metals	Relatively high
High-speed Steel	Good strength and toughness, better than cemented carbide	Low	Suitable for machining steel and non-ferrous metals with general hardness. The machining efficiency for high-hardness materials is low.	Low
Ceramic Tool	Relatively poor strength and toughness, brittle, and prone to chipping	High, enabling high-speed cutting	Suitable for machining high-hardness materials, cast iron, and some difficult-to-machine materials, but not suitable for machining materials with high toughness	Relatively high, with high requirements for the production process
Superhard Tool	The strength of PCD tool is low, and the strength of CBN tool is relatively good	Very high, especially when machining high-hardness materials	PCD tool is suitable for machining non-ferrous metals, non-metallic materials, etc. CBN tool is suitable for machining high-hardness alloy steel, high-speed steel, cast iron, etc.	Very high, with a complex manufacturing process

5. Advantages of cemented carbide cutting tools in CNC processing

(1) High-speed cutting capability

Due to their high hardness and good thermal stability, cemented carbide cutting tools can withstand the high temperature and high pressure generated by high-speed operation in CNC processing. This makes it suitable for high-speed cutting processes, significantly improving processing efficiency, significantly shortening processing time compared to traditional tools, and meeting the needs of modern manufacturing for efficient production. ​

(2) Precision machining adaptability​

The sharpness and wear resistance of the cutting edge of the tool are key factors in achieving precision machining. The cutting edge of cemented carbide cutting tools is of high quality and can maintain a stable geometric shape during long-term cutting, effectively reducing processing errors and achieving high-precision dimensional control. Whether it is fine processing of tiny parts or precision milling of complex contours, cemented carbide tools can provide excellent processing accuracy and ensure that the products meet strict quality standards.

6. Specific applications in the industry

(1) Automobile manufacturing industry

In the processing of key components such as automobile engines and transmissions, cemented carbide cutting tools are widely used. For example, when machining engine cylinders, cemented carbide face milling cutters and boring cutters are used for milling and boring, which can ensure the dimensional accuracy and surface quality of the cylinder bore and improve the performance and reliability of the engine;

When machining automobile gears, cemented carbide hobs and gear shaping cutters can efficiently and accurately process the gear tooth shape to ensure the stability of the transmission system.

Carbide hobs are machining gears

(2) Aerospace industry

The aerospace field has extremely stringent requirements for the precision and reliability of parts. Carbide cutting tools are often used to process key parts such as aircraft engine blades and landing gear made of difficult-to-process materials such as titanium alloys and nickel-based alloys.

Through high-speed cutting and precision machining, carbide tools can meet the strict dimensional accuracy and surface quality requirements of aerospace parts and ensure the safety performance of aircraft.

(3) Mold manufacturing industry

Mold manufacturing involves the processing of a large number of complex cavities and high-precision surfaces. Carbide end mills and ball end mills play an important role in mold milling. Through the precise control of CNC machining centers, various complex mold cavities can be processed, improving the processing efficiency and surface quality of the mold, shortening the mold manufacturing cycle, and reducing production costs.

(4) Electronic manufacturing industry

The electronic manufacturing field has a strong demand for the processing of tiny parts and precision structures. With high precision and high wear resistance, carbide micro-tools are suitable for processing electronic chip packaging molds, precision hardware parts, etc.

For example, micro carbide milling cutters can be used to machine micron-level precision cavities and grooves on chip packaging molds, meeting the development trend of miniaturization and precision of electronic components.

7. Summary

In summary, carbide cutting tools, with their unique performance characteristics, have shown strong advantages in many metal material processing and CNC processing stages, and are widely used in key manufacturing links in various industries.