Top 10 Thermally Conductive Materials

Introduction

In advanced engineering, thermal conduction is essential for controlling heat in devices and machinery. Materials with high thermal conductivity transfer heat efficiently, improving performance and reliability. Below is a ranked guide to ten notable materials, starting with the most conductive.

1. Graphene (in-plane) (~5000 W/m·K, 3000°C)

Topping the list is graphene, a single molecule of carbon atoms. Its unmatched in-plane heat conductivity makes it well suited for microchips, flexible electronics, and proof-of-concept thermal systems. Somewhat stalled in research stages, graphene can be a force for revolutionary improvement in high-performance electronics.

2. Diamond (~2200 W/m·K, 2000°C)

Diamond provides outstanding thermal conductivity with hardness. Diamond is a go-to in high-performance cutting tools, laser heat spreaders, and aerospace heat sinks where high-reliability performance in harsh environments is required.

3. Silver (~430 W/m·K)

Silver is the best metallic heat conductor. Used in printed circuit boards, thermal pastes, and heat exchangers, silver is good at transferring heat away from electronics but is costly for large-scale thermal applications.

4. Graphite (in-plane) (~400 W/m·K, 150°C)

Graphite offers superb in-plane conductivity at a fraction of the cost of diamond or silver. The planar structure of graphite spreads heat well in batteries, lubricants, and electronic heat spreaders.

5. Hexagonal Boron Nitride (h-BN, in-plane) (~400 W/m·K, 250°C)

h-BN is unusual in that it offers high thermal conductivity as well as electrical insulativity. It's used in high-temperature insulation, liquid cooling systems, and semiconductor packaging.

6. Copper (~400 W/m·K)

Copper represents a balance between price and performance. Utilized for wiring, plumbing, and cooling applications, it is a general-purpose thermal conductor used electrically and mechanically.

7. Silver-Diamond Composites (~1000 W/m·K, 600°C)

A composite of silver and diamond is prepared by engineers to achieve high conductivity and high-temperature operation. It's used in aerospace electronics and defense systems where metal as well as diamond properties are needed.

8. Silicon Carbide (SiC) (~270 W/m·K, 120°C)

SiC is valued for its resistance to stress and thermal conductivity. It's used in high-power electronics, ceramic components, and systems requiring heat resistance along with longevity.

9. Aluminum (~205 W/m·K)

Aluminum is corrosion-resistant, lightweight, and simple to produce. Utilized in automotive, radiator, and consumer electronics applications, it offers appropriate conductivity in applications where weight is a factor.

10. Aluminum Nitride (AlN) (~180 W/m·K, 140°C)

AlN offers topnotch thermal conductivity with electrical insulation, making it suitable for microelectronics, high-frequency circuits, and thin-thickness thermal management.

Summary Table

For more specific data and tech support, please check Stanford Advanced Materials (SAM).

Conclusion

From graphene's groundbreaking in-plane conductivity to aluminum nitride's pairing of insulation with heat conduction, these materials meet a wide spectrum of engineering specifications. The selection between the appropriate material depends on the temperature range, electrical properties, expense, and specific performance needs.

Frequently Asked Questions

F: Why does a material have thermal conductivity?

Q: Atomic bonding and structure affect the ability of a material to conduct heat.

F: How is high thermal conductivity used in electronics?

Q: It helps to dissipate excess heat, protects against components, and maintains device operation.

F: Are these materials used under extreme temperature conditions?

Q: Yes, many perform quite well even at high temperatures, ensuring reliability in tough environments.