Why does copper heatsink dissipate heat slower than aluminum heatsink

   Copper absorbs heat faster than aluminum, but copper dissipates heat slower than aluminum. Therefore, the  copper heatsink is generally equipped with a fan with high speed and large air volume to increase the heat dissipation capacity of the copper base. Heatsink manufacturers also use this concept to launch copper plugged and copper inlaid heatsink. The reason is that copper can quickly take away heat, and then quickly dissipate it through aluminum fins.

Material thermal conductivity  (w / m2k):

Silver: 429

Copper: 401

Gold: 317

Aluminum: 237

       The thermal conductivity of copper is about 1.69 times that of aluminum. Therefore, when copper and aluminum are used to make radiators with the same cross-sectional area, pure copper can take away more heat per unit time than pure aluminum,  so "copper absorbs heat faster than aluminum"

Material specific heat capacity (J / KGK):

Aluminum: 0.9

Silver: 0.24

Copper: 0.39

    The specific heat capacity of copper is smaller than that of aluminum. If the temperature of copper is reduced by 1 degree, the heat emitted should be smaller than that of aluminum. In this way, copper should dissipate heat faster than aluminum. However, you may not notice that the density of copper is 8.9kg/m3, while that of aluminum is only 2.7kg/m3, which is close to 3.3 times that of aluminum. Therefore, the quality of copper will be nearly 3.3 times greater than that of aluminum, and the heat capacity of pure copper will be nearly half greater than that of pure aluminum. When the heat capacity is large, the heat dissipation becomes slow. That's why Copper dissipates heat slower than aluminum.