Graphite Blocks and Rods

Graphite blocks and rods are solid pieces of graphite, shaped into various dimensions and forms for industrial and commercial applications. They are known for their excellent thermal and electrical conductivity, high thermal resistance, and chemical inertness. These properties make graphite blocks and rods versatile materials used in numerous high-temperature and high-stress environments.

Specifications

1. Purity: Graphite blocks and rods typically have high carbon content, often exceeding 99%. The purity can vary based on the intended application.

2. Dimensions:

   • Blocks: Graphite blocks can vary widely in size, from small blocks of a few centimeters to large blocks several meters in length and width.
   • Rods: Graphite rods are available in various diameters and lengths. Common diameters range from a few millimeters to several centimeters, and lengths can vary from a few centimeters to several meters.

3. Grades: Graphite blocks and rods are available in different grades, depending on the specific requirements of the application:

   • Electrode Grade: Used in electric arc furnaces and other high-current applications.
   • Fine-Grain Graphite: Used for precision applications requiring high strength and fine detail.
   • Isostatic Graphite: Offers uniform properties and is used in high-performance applications.

4. Mechanical Properties:

   • Density: Typically ranges from 1.6 to 1.9 g/cm³.
   • Flexural Strength: Generally ranges from 30 to 50 MPa.
   • Compressive Strength: Typically around 70 to 100 MPa.
   • Young's Modulus: Usually between 8 to 15 GPa.

5. Thermal and Electrical Properties:

   • Thermal Conductivity: High, generally ranging from 80 to 150 W/m·K.
   • Electrical Conductivity: High, making them suitable for electrical applications.
   • Thermal Expansion Coefficient: Low, typically between 4 to 8 x 10^-6 /°C.

Usage Applications

1. Electrodes for Electric Arc Furnaces (EAF): Graphite rods are used as electrodes in EAF for steelmaking. They conduct the electrical current that generates the high temperatures needed to melt scrap metal.

2. Heat Exchangers: Graphite blocks are used in heat exchangers for their excellent thermal conductivity and resistance to corrosion, particularly in chemical processing industries.

3. Molds and Casting: Graphite blocks and rods are used to make molds for casting metals, plastics, and glass. Their ability to withstand high temperatures and their machinability make them ideal for this purpose.

4. High-Temperature Furnaces: Graphite blocks are used as structural components in high-temperature furnaces, including insulation, furnace linings, and heating elements.

5. Chemical Industry: Graphite rods and blocks are used as anodes in electrochemical processes, such as electrolysis and electroplating, due to their high conductivity and chemical inertness.

6. Semiconductor Industry: In the semiconductor industry, graphite blocks are used to create crucibles for crystal growth and other high-purity applications requiring precise temperature control.

7. Nuclear Industry: Graphite rods are used as moderators in nuclear reactors to slow down neutrons, facilitating the nuclear fission process.

8. Aerospace Industry: Graphite blocks and rods are used in aerospace applications for their lightweight, high strength, and thermal stability properties.

9. Mechanical Seals and Bearings: Graphite blocks and rods are used to manufacture mechanical seals and bearings that can operate at high temperatures and in corrosive environments.

10. Renewable Energy: In renewable energy systems, such as solar thermal collectors, graphite blocks are used for their high thermal conductivity and heat storage capabilities.

11. Electronics and Electrical Applications: Graphite rods are used in the manufacture of various electronic components, including resistors, batteries, and conductive coatings.

12. Lubrication: Graphite blocks and rods are used in lubrication applications, particularly in high-temperature environments where traditional lubricants would fail.

Graphite blocks and rods are essential materials in a wide range of industries due to their unique combination of thermal and electrical conductivity, high-temperature stability, and chemical resistance. Their versatility allows them to be used in applications from steelmaking and chemical processing to electronics and aerospace.