Top 10 Materials with the Highest Thermal Conductivity-Top 10 Thermally Conductive Materials

Thermally ConductiveThermally Conductive is a measure of a material's ability to transfer heat. Materials with high thermal conductivity can efficiently transfer heat and easily absorb heat from the environment. Poor thermal conductors impede the flow of heat and slowly pick up heat from the surroundings. The thermal conductivity of a material is measured in Watts per meter per Kelvin (W/m-K) according to S.I (Systems International) guidelines.

The top 10 thermal conductivity materials measured and their values are summarized below. Since thermal conductivity varies depending on the equipment used and the environment in which the measurements were obtained, these conductivity values are averages.

Naturally occurring thermally conductive materials #

1. Diamonds - 2000 - 2200 W/m-K #

Diamond is nature's best thermal conductor, with a measured electrical conductivity five times higher than copper, the most manufactured metal in the United States. Diamond atoms consist of a simple carbon skeleton, an ideal molecular structure for efficient heat transfer. Typically, materials with the simplest chemical composition and molecular structure have the highest thermal conductivity values.

Diamonds are an important part of many modern handheld electronic devices. Their role in electronics is to promote heat dissipation and protect sensitive computer components. The high thermal conductivity of diamonds has also proven useful when determining the authenticity of gemstones in jewelry. Adding small amounts of diamond to tools and technology can have a dramatic impact on thermal conductivity.

2. Silver - 429 W/m-K #

Silver is a relatively cheap and abundant conductor of heat. Silver is a component of many electrical appliances and is one of the most versatile metals due to its ductility. U.S.-made 35% of silver is used in power tools and electronics (U.S. Geological Survey Mineral Community 2013). The byproduct of silver, silver paste, has increased in demand due to its use in environmentally friendly energy alternatives. Silver paste is used in the production of photovoltaic cells, which are the main component of solar panels.

3. Copper - 398 W/m-K #

Copper is the most commonly used metal for manufacturing conductive appliances in the United States. Copper has a high melting point and moderate corrosion rate. It is also a very efficient metal for minimizing energy loss during heat transfer. Metal pots and pans, hot water pipes, and automobile radiators are all appliances that utilize copper's conductive properties.

4. Gold - 315 W/m-K #

Gold is a rare and expensive metal used for specific conductive applications. Unlike silver and copper, gold rarely tarnishes and can withstand conditions of extensive corrosion.

5. Aluminum Nitride - 310 W/m-K #

Aluminum nitride is often used as a replacement for beryllium oxide. Unlike beryllium oxide, aluminum nitride does not pose a manufacturing health hazard, but still displays similar chemical and physical properties to beryllium oxide. Aluminum nitride is one of the few materials with high thermal conductivity and electrical insulation. It has exceptional resistance to thermal shock and acts as an electrical insulator in mechanical chips.

6. Silicon Carbide - 270 W/m-K #

Silicon carbide is a semiconductor that consists of a balanced mixture of silicon and carbon atoms. When manufactured and fused together, silicon and carbon combine to form an extremely hard and durable material. This mixture is commonly used as an ingredient in automobile brakes, turbines, and steel mixtures.

7. Aluminum - 247 W/m-K #

Aluminum is often used as a cost-effective alternative to copper. Although not as conductive as copper, aluminum is abundant and easy to work with because of its low melting point. Aluminum is an important component of L.E.D lamps (Light Emitting Diodes). Copper-aluminum mixtures are becoming increasingly popular because they can take advantage of the properties of both copper and aluminum and can be manufactured at a lower cost.

8. Tungsten - 173 W/m-K #

Tungsten has a high melting point and low vapor pressure, making it an ideal material for appliances exposed to high-intensity electricity. Tungsten's chemical inertness allows it to be used as an electrode as part of an electron microscope without changing the current. It is also frequently used in components of light bulbs and cathode ray tubes.

9. Graphite 168 W/m-K #

Graphite is an abundant, low-cost and lightweight alternative to other carbon isomers. It is often used as an additive in polymer blends to enhance their thermal conductivity. Batteries are a common example of appliances that utilize graphite's high thermal conductivity.

10. Zinc 116 W/m-K #

Zinc is one of the few metals that can be easily combined with other metals to form metal alloys (mixtures of two or more metals). Zinc appliances are made from a zinc alloy in the USA 20%. Galvanizing uses manufactured pure zinc from 40%. Galvanizing is the process of applying a zinc coating to steel or iron designed to protect the metal from weathering and rusting.

Source:

• https://thermtest.com/thermal-resources/top-10-resources/top-10-thermally-conductive-materials
• https://thermtest.com/thermal-resources/materials-database
• https://www.unitconverters.net/thermal-conductivity-converter.html Unit Conversion

Artificial surface treatment materials #

• DLC Diamond-Like Coating - Nano-coating manufactured by PVD process using vacuum coating technology. Possesses good insulation and thermal conductivity
• Al2O3 Aluminum Oxide Coating - Nano-coating made by CVD process. It is a more common composite functional film with good insulation + thermal conductivity. Compared with thermal spraying, film thickness control and bonding will have obvious advantages. But the high price is difficult to popularize. Thermal conductivity: 23-32 (W/m*k)
• HBN Hexagonal Boron Nitride Coating - 33 (W/m*k), the best ceramic coating for thermal conductivity above 500°C environment. Also the best ceramic insulation at high temperatures (breakdown voltage 3kv/mm). Conventional chemical inertness, low coefficient of friction of 0.16. Resistant to oxidation, 900°C with oxygen, 2000°C without oxygen. Nasco's TiB2 composite vacuum coating process can be customized with super temperature resistant and super hard nano coatings.
• BeO Beryllium Oxide - Similar thermal conductivity to purple copper. Powder is highly toxic. volatilization begins at 1000°C. Beginning to be phased out.