Which of these materials is the best conductor of heat?

Among common metals, aluminum and copper have the highest thermal conductivity, with values of 205W/mK and 401W/mK respectively, compared to steel’s 50W/mK. These two materials are the most commonly used in the production of computer heatsinks. While copper is superior in heat conduction, aluminum is a more cost-effective, lighter, and easier to work with alternative for manufacturers.

Although there are materials with higher thermal conductivity, such as silver with 429W/mK (used in Arctic Silver thermal paste), diamond with 2300W/mK (used in IC Diamond thermal paste), and graphene with 5300W/mK, they are not practical for mass-producing heatsinks. Graphite is also occasionally used as it is lighter than copper and aluminum while offering thermal performance in between the two.

Diamond stands out with its exceptional thermal conductivity of 2200-2500 W/mK, but its high cost and difficulty in production make it impractical for mass-produced heatsinks. Silver, being the best metallic heat conductor with 430 W/mK, is also costly and not commonly used in mainstream cooling solutions due to its softness and potential durability issues.

Copper, with a thermal conductivity of 400 W/mK, is another excellent heat conductor that is more affordable and durable than silver. Its high density allows for efficient heat absorption and dissipation, making it a popular choice for heatsinks. However, its weight can be a drawback in certain applications like laptops or small form factor PCs.

Aluminum, with a thermal conductivity of around 205 W/mK, is the most widely used material for heatsinks due to its balance of cost, weight, and performance. While not as effective as copper or silver in heat conduction, aluminum’s lightweight nature, ease of shaping, and corrosion resistance make it a preferred option for many manufacturers.

The choice of heatsink material typically involves considering factors such as thermal conductivity, weight, durability, and cost.