Tungsten carbide (WC)—also known as “Widia,” a name derived from the German phrase *wie diamant* (“like diamond”)—is one of the hardest carbon-based compounds. Typically gray in color, tungsten carbide powder can be sintered and pressed to form jewelry, cutting tools, and engineering machinery components, or used as a specialized coating for various high-performance parts. So, what kind of material is tungsten carbide? What are its properties and hardness levels? What are the advantages and disadvantages of tungsten carbide thermal spraying? Here is a detailed overview of the fundamentals of tungsten carbide materials.
What Kind of Material Is Tungsten Carbide?
“Tungsten carbide” is a term used for a broad category of alloys composed of tungsten carbide itself, a metallic binder, and other added carbides (such as TiC and TaC). Cobalt and nickel are the two most common metallic binders. The binder influences the material’s hardness, toughness, and chemical compatibility. Depending on the desired properties, the binder content in the finished material can range from 3% to 20%.
Tungsten carbide is an extremely versatile material; alloying allows for a wide range of properties. Its exceptional hardness enables it to shape and cut almost any other material, while its high-temperature resistance allows for high-speed operation, maximizing its value as a cutting tool.
For this reason, it is increasingly used in applications involving various steel alloys—ranging from standard types to highly corrosion-resistant varieties—in addition to its use on materials requiring extreme hardness (such as manganese steel or tool steel).
Due to its low ductility and high mechanical strength, tungsten carbide is also applied as a coating on components subject to continuous friction and requiring high wear resistance—such as bearings or rotating elements. This is typically achieved using thermal spray systems, such as HVOF (High-Velocity Oxy-Fuel).
What Is the Hardness of Tungsten Carbide?
As one of the hardest materials available, tungsten carbide has a hardness rating of between 8.5 and 9.5 on the Mohs scale, surpassed by only a very few materials, such as diamond. This material is created by combining carbon and tungsten with a small amount of cobalt; through a sintering process, it forms a type of cermet (ceramic-metal composite) widely regarded as one of the most durable compounds in the industry.
Tungsten carbide is produced by sintering metal powders at a pressure of 1,000 atmospheres, using cobalt powder as a binder—cobalt itself being a very hard metal. Tungsten carbide possesses extreme hardness; it is commonly manufactured into cutting tools (capable of cutting stainless steel), drill bits, and armor-piercing projectile cores. With a Vickers hardness reaching up to 1800 HV, it was the hardest material available at the time of its development. Its hardness is essentially comparable to that of sapphire.
Tungsten carbide offers genuine, intrinsic hardness; unlike titanium alloys or other metals that rely on surface hardening treatments, tungsten carbide maintains the same hardness throughout its entire structure. Furthermore, due to its exceptional hardness, it achieves a brilliant luster when polished.
What are the applications of tungsten carbide?
Compared to tool steel, tungsten carbide offers superior hardness; compared to technical ceramics, it offers superior toughness. Consequently, it is utilized across many industries. Given these outstanding properties, tungsten carbide is most frequently associated with metal-cutting tools used for sawing, milling, and turning. Many are surprised to learn that it is also commonly used in fluid dispensing and flow applications, as it demonstrates an excellent service life when exposed to erosive wear. Its enhanced wear resistance extends the lifespan of components—such as nozzles—in industries ranging from waterjet cutting and oil and gas to electronics.
Pros and cons of tungsten carbide spraying
Advantages of tungsten carbide spraying: Good thermal stability, excellent wear resistance, superior impact resistance, and good machinability.
Disadvantages of tungsten carbide spraying: High cost and strict requirements for the application environment.
Advantages of supersonic spraying for tungsten carbide coatings:
1. Higher velocity. In supersonic spraying, the particle velocity reaches approximately five times the speed of sound; this results in superior processing quality and ensures high processing efficiency. During the spraying process, the powder velocity can be rapidly increased, effectively ensuring the density and strength of the coating; performance reliability is thus guaranteed.
2. Superior bonding strength. Due to the unique nature of the supersonic tungsten carbide spraying process, the resulting coating is highly dense with low porosity, ensuring excellent surface performance. Furthermore, the process yields exceptionally high bonding strength, resulting in superior product quality and making it a highly desirable choice.
3. No workpiece deformation. Supersonic tungsten carbide spraying ensures that the workpiece remains undeformed during high-speed operation, guaranteeing practical reliability.
Post time: Jun-30-2026