Cemented Carbide: A Comprehensive Analysis of Properties and Applications

In the field of industrial manufacturing, cemented carbides are hailed as the “teeth of industry” due to their unique properties. This material, produced via powder metallurgy from refractory metal carbides and a metallic binder, has evolved since 1923—when German scientist Schulte first invented tungsten carbide–cobalt alloys—into an indispensable foundational material for modern industry. Its applications have expanded from conventional machining to cutting-edge sectors such as aerospace, new energy, and electronic information, making it a key indicator of a nation’s industrial sophistication.

I. Core Characteristics of Cemented Carbides

The physical properties of cemented carbides exhibit a pronounced bimodal character. Their hardness can reach 86–93 HRA (equivalent to 69–81 HRC), and they retain a hardness above 60 HRC even at elevated temperatures of 1,000°C, making them the material of choice for high‑temperature cutting applications. Microstructural analysis reveals that these materials consist of tungsten carbide (WC) grains ranging from 0.5 to 5 μm in size, embedded in a cobalt (Co) binder phase, forming a composite structure akin to “reinforced concrete”: the WC grains provide hard‑bearing support, while the cobalt phase imparts the necessary toughness.

In terms of chemical stability, cemented carbides exhibit excellent corrosion resistance. In solutions with a pH ranging from 2 to 12, their corrosion rate is less than one-tenth that of high-speed steel, owing to the dense oxide film that forms on the surface of WC grains. However, it should be noted that in oxidizing atmospheres, when the temperature exceeds 800°C, the cobalt phase undergoes preferential oxidation, leading to embrittlement of the material—this constitutes the primary limitation hindering its high-temperature applications.

The mechanical properties exhibit pronounced anisotropy. The longitudinal compressive strength can reach 6,000 MPa, twice that of high-speed steel; however, the transverse flexural strength is only 1,000–3,000 MPa, about one-third of that of high-speed steel. This characteristic necessitates optimizing grain orientation in tool design; gradient sintering is commonly employed to refine surface grains and enhance impact resistance.

II. Material Systems and Manufacturing Processes

Based on compositional differences, cemented carbides are classified into three major families: tungsten–cobalt (YG), tungsten–titanium–cobalt (YT), and tungsten–titanium–tantalum (niobium) (YW). Among these, YG6X (containing 6% cobalt), which combines excellent toughness with outstanding wear resistance, has become the standard material for cast‑iron machining; YT15 (with 15% titanium carbide), owing to its superior red hardness, is widely used for the finish machining of steel parts; and YW2, by incorporating tantalum carbide, raises the applicable cutting speed to over 150 m/min.

Manufacturing processes directly influence material properties. Modern production employs vacuum low-pressure sintering, which, at 1450°C, induces the formation of an eutectic liquid phase in the cobalt matrix, thereby promoting a uniform distribution of WC grains. Grain-size control is a critical step: ultrafine-grained materials (0.2–0.5 μm) can achieve a hardness of up to 93 HRA, but their impact resistance decreases by approximately 30%; by contrast, coarse-grained materials (3–5 μm) exhibit improved impact resistance at the expense of hardness. The addition of 0.5% chromium carbide effectively suppresses abnormal grain growth during sintering.

III. Typical Application Scenarios

In the cutting tools sector, cemented carbide holds a dominant position. In the machining of automotive engine cylinder blocks, PVD-coated carbide tools can boost machining efficiency by a factor of four and extend tool life by a factor of ten. For deep-hole machining of electric‑vehicle motor housings, the chip‑resistance performance of YW‑grade general‑purpose alloys is essential. According to 2025 data, 85% of global CNC cutting tools feature cemented carbide substrates, with coated tools accounting for more than 60% of this share.

Geological and mining tools represent the second-largest application area for cemented carbides. YW3 alloy is used in roller‑cone drill bits, which, when operating in rock formations with a hardness of up to f18, deliver a service life 20 times longer than that of steel‑toothed drill bits. Coal‑mining shearer picks employ YG11C alloy; by optimizing the gradient distribution of cobalt content, impact resistance is improved by 50%. By 2026, China’s production of cemented carbides for geological and mining applications is expected to reach 13,000 tonnes, accounting for 38% of the global market share.

In the mold‑making sector, cemented carbides are gradually replacing conventional tool steels. For cold‑heading dies, using YG20C alloy has increased die life from 5,000 cycles to 500,000 cycles when producing M12 bolts. In the wire‑drawing die field, ultrafine‑grained cemented carbides can reduce the surface roughness of stainless steel wire to below Ra 0.05 μm, meeting the stringent requirements of the semiconductor industry.

IV. Trends in Technological Development

In response to the demands of high-end manufacturing, cemented carbides are evolving toward greater functionality and智能化. Nanocrystalline cemented carbides achieve a hardness exceeding 95 HRA by reducing WC grain sizes to below 100 nm, while maintaining a flexural strength of 800 MPa. Functionally graded materials (FGMs), by precisely controlling the distribution of the cobalt phase, enable tool surfaces with a hardness of 92 HRA while preserving a core flexural strength of 1,200 MPa.

In the field of new energy, cemented carbides are demonstrating new application potential. For diamond wire saws used in photovoltaic silicon wafer cutting, a YG6X alloy matrix is employed, reducing cutting loss to 80 μm. In hydrogen storage and transportation, high-pressure valve seats at hydrogen refueling stations utilize tungsten–cobalt–nickel-based cemented carbides, maintaining leak‑free performance over 100,000 cycles at 70 MPa.

From its laboratory origins in 1923 to its status as a cornerstone material underpinning modern industry, the century-long evolution of cemented carbide underscores the pivotal role of materials innovation in driving industrial transformation. With the advent of emerging technologies such as 3D printing and atomic layer deposition, this “industrial tooth” is now sprouting sharper “new teeth,” providing critical material support for the era of intelligent manufacturing.

Tel: +86-315-7172865

Whatsapp: +86-19358204839

E-mail: 461982296@qq.com

Add: High-tech industrial Development Zone, Qian'an City, Hebei Province