Tungsten vs. Tungsten Carbide

Attribute	Tungsten	Tungsten Carbide
Chemical Symbol	W	WC
Atomic Number	74	N/A
Atomic Mass	183.84 g/mol	N/A
Physical State	Solid	Solid
Color	Grayish-White	Gray
Melting Point	3,422 °C	2,870 °C
Boiling Point	5,555 °C	6,000 °C
Density	19.25 g/cm³	15.63 g/cm³
Hardness	7.5 (Mohs)	9-9.5 (Mohs)
Electrical Conductivity	Low	Low
Thermal Conductivity	173 W/m·K	80-120 W/m·K
Corrosion Resistance	High	High
Applications	Electrical contacts, filaments, alloys	Cutting tools, wear-resistant parts

Introduction

Tungsten and tungsten carbide are two materials widely used in various industries due to their exceptional properties. While they share similarities, they also have distinct attributes that make them suitable for different applications. In this article, we will delve into the characteristics of tungsten and tungsten carbide, exploring their strengths, weaknesses, and applications.

Tungsten

Tungsten, known for its high melting point and density, is a chemical element with the symbol W on the periodic table. It is a hard, brittle, and steel-gray metal that is often extracted from minerals like scheelite and wolframite. Tungsten possesses several remarkable attributes:

• High Melting Point: Tungsten has the highest melting point of all metals, reaching a staggering 3,422 degrees Celsius (6,192 degrees Fahrenheit). This exceptional heat resistance makes it ideal for applications involving extreme temperatures, such as aerospace components and high-temperature furnaces.
• High Density: With a density of 19.3 grams per cubic centimeter, tungsten is one of the densest elements. This density contributes to its excellent mechanical properties, including high strength and durability. It is commonly used in the production of heavy machinery, electrical contacts, and radiation shielding.
• Hardness: Tungsten is renowned for its exceptional hardness, ranking 7.5-8 on the Mohs scale. This hardness allows it to resist wear, making it suitable for applications that require resistance to abrasion, such as cutting tools, drill bits, and armor-piercing ammunition.
• Corrosion Resistance: Tungsten exhibits excellent resistance to corrosion, even in harsh environments. This property makes it a preferred choice for chemical processing equipment, marine applications, and electrical contacts where exposure to corrosive substances is common.
• Electrical Conductivity: While not as conductive as copper or silver, tungsten still possesses good electrical conductivity. It is often used in electrical contacts, filaments for incandescent light bulbs, and various electronic components.

Tungsten Carbide

Tungsten carbide, on the other hand, is a compound consisting of tungsten and carbon atoms. It is commonly referred to as a cemented carbide due to its manufacturing process, which involves sintering tungsten carbide powder with a binder metal, typically cobalt or nickel. Tungsten carbide exhibits several unique properties:

• Exceptional Hardness: Tungsten carbide is renowned for its extreme hardness, ranking 9 on the Mohs scale. This hardness surpasses that of most other materials, including titanium, steel, and even natural diamonds. It is widely used in cutting tools, mining equipment, and wear-resistant parts.
• High Strength: The combination of tungsten carbide's hardness and its strong metallic bonds results in exceptional strength. It can withstand heavy loads, making it suitable for applications that require high strength and durability, such as drill bits, saw blades, and industrial machinery components.
• Heat Resistance: Tungsten carbide exhibits excellent heat resistance, allowing it to maintain its hardness and strength even at high temperatures. This property makes it ideal for cutting tools used in high-speed machining, metalworking, and other applications involving intense heat.
• Wear Resistance: Due to its hardness and strength, tungsten carbide is highly resistant to wear and abrasion. It can withstand prolonged use without significant loss of performance, making it suitable for applications that involve high levels of friction, such as seals, bearings, and nozzles.
• Chemical Stability: Tungsten carbide is chemically stable and resistant to most acids, alkalis, and other corrosive substances. This stability allows it to maintain its integrity in harsh environments, making it suitable for chemical processing equipment, valves, and pump components.

Applications

Both tungsten and tungsten carbide find extensive applications across various industries. Tungsten is commonly used in:

• Electrical contacts and filaments
• Aerospace components
• High-temperature furnaces
• Heavy machinery
• Radiation shielding

On the other hand, tungsten carbide is widely employed in:

• Cutting tools
• Drill bits
• Saw blades
• Mining equipment
• Wear-resistant parts

Conclusion

In conclusion, tungsten and tungsten carbide are two remarkable materials with distinct attributes that make them suitable for various applications. Tungsten possesses exceptional heat resistance, high density, hardness, corrosion resistance, and electrical conductivity. On the other hand, tungsten carbide exhibits extreme hardness, high strength, heat resistance, wear resistance, and chemical stability. Understanding the unique properties of these materials allows industries to choose the most appropriate one for their specific needs, ensuring optimal performance and longevity in their applications.