Thermal material for CPU cooler heatsink
Working principle of CPU heatsink:
Taking Intel downwind heatsink as an example. The yellow circle at the bottom of the heatsink is made of copper. It is in direct contact with the CPU. Through the characteristics of easy heat conduction of metal, the heat generated by the CPU can be quickly taken away, so that the heat can be transmitted to the surrounding cooling fins, and then the fins can be in large-area contact with the air and the help of the fan, so as to achieve the effect of heat dissipation.
Characteristics of copper and aluminum materials:
Most heatsinks are made of copper or aluminum. Is copper or aluminum better? Normally, we have to look at the two physical properties of its material: thermal conductivity and specific heat.
The thermal conductivity of copper at room temperature is 401 w / M K; Aluminum is 237 w / M K. The higher the number, the better the heat conduction. Therefore, the heat conduction effect of copper is nearly twice that of aluminum. The specific heat of copper is 0.385 J / G K; The specific heat of aluminum is 0.897 J / g K. The smaller the specific heat is, the easier the temperature is to rise or fall. The specific heat of copper is about half that of aluminum, so the temperature drops faster and the heat dissipation is more efficient.
Why do most radiators use a mixture of copper and aluminum?
1. The mixed material of copper and aluminum is used because we can't judge the effect of radiator simply by specific heat. The specific heat should be compared on the premise of the same weight. The density of copper and aluminum is completely different, that is to say, their volume is different under the same weight, so the heat dissipation area is also different.
2. Taking volume into account, the specific heat is replaced by heat capacity. The density of copper (8.9) is more than three times higher than that of aluminum (2.7), so the specific heat should be multiplied by the density to calculate the heat capacity. After multiplying, the result is that the heat capacity of copper is 3.43 J / GV; The heat capacity of aluminum is 2.42 J / GV. In other words, under the same volume, aluminum is easier to cool down.
3. The heat conduction of copper is three times faster than that of aluminum, but under the same volume, the cooling efficiency of aluminum is 1.5 times higher than that of copper. Therefore, they give full play to their respective advantages. Copper with faster heat conduction is used as the base in contact with CPU to conduct heat quickly; Faster cooling aluminum is used as radiator fins to quickly take away heat.
For CPU heatsinks, copper and aluminum have their own advantages. Copper conducts heat quickly and aluminum cools down quickly. Therefore, most heatsink coolers we see, including tower heatsinks, adopt the design of copper bottom + aluminum fins, which can maximize the heat dissipation efficiency of CPU.
