Why do copper heat sinks dissipate more slowly than aluminum heat sinks

Copper absorbs heat faster than aluminum, and copper loses heat faster than aluminum. So the copper heat sink base is equipped with the fan of high rotating speed, big air volume commonly, increase the heat dissipation capacity of copper base. The heat sink manufacturer also borrowed this idea to launch plug copper, set copper heat sink, reason is to use copper to take away heat quickly, send out quickly through aluminous qualitative fin next

 After all, what is the scientific basis for the statement that copper absorbs heat faster than aluminum, and copper loses heat faster than aluminum? Perhaps you can clearly say a few, today small make up to tell you the basic principle of this phenomenon.

Thermal conductivity K (W/m2K)

Silver 429

Copper 401

Gold 317

Aluminum 237

The popular definition of heat transfer coefficient is "heat per unit area per unit time at unit temperature difference", the unit is J/m2ks, or W/m2k, where J is the unit joule of heat, m2 is the unit square meter of area, K is the unit kelvin of temperature, can also be replaced by C on the Celsius scale, s is the unit second of time. From above the heat conduction coefficient of copper is about 1.69 times that of aluminium, because this uses copper and aluminium to make the heat sink of same sectional area, inside unit time pure copper can take away more heat than pure aluminium, "copper absorbs heat faster than aluminium", the preceding half sentence has been proved.

Material specific heat capacity J/kgK

Aluminum 0.9

Silver 0.24

Copper 0.39

Copper loses heat as fast as aluminum, which is true. Proving this leads to another important thermodynamic parameter: specific heat. Anyone who has studied high school physics knows that specific heat is defined as "the amount of heat required to raise the temperature of a substance by one degree per unit mass," in units of J/kgK. You can also see from the table above that the specific heat capacity of copper is smaller than that of aluminum. Copper should lose less heat than aluminum if it loses 1 degree of temperature. In this way, copper should lose heat faster than aluminum. However, you may not have noticed that the density of copper is 8.9kg/m3, while that of aluminum is only 2.7kg/m3, which is nearly 3.3 times that of aluminum. Therefore, if you make a heat sink of the same volume, the mass of copper is nearly 3.3 times larger than that of aluminum, and the heat capacity of pure copper is still nearly half that of pure aluminum.The larger the heat capacity, the slower the heat dissipation.Through the explanation of the above theory, we have also found out the reason why "copper loses heat faster than aluminum".　　

We fundamentally understand that "copper absorbs heat faster than aluminum, copper does not dissipate heat as fast as aluminum". When choosing heat sink later, can apply this theory, if choose pure copper heatsink, should choose to equip with rotating speed taller, the fan product with larger air volume, avoid copper heat to send out not, generation dissipates heat bottleneck.