Comparison of heat dissipation performance between magnesium alloy and aluminum alloy

1, according to the formula: Q=dvC△t(where Q - heat; D = proportion; V = volume; C= specific heat capacity; △t =(t1-t2) temperature change;) When AZ91D and A380 with the same volume and shape receive the same heat Q, the temperature ratio of change between them is △tMg /△tAl =2.74x0.23/1.81x1.05=1/3; That is, magnesium alloy AZ91D is 1/3 of aluminum alloy A380;

2. AZ91D thermal conductivity 54W/mk; A380 thermal conductivity 100W/mk; Difference by a factor of one. Means for the same volume and shape of AZ91D and A380 material radiator. The A380 is twice as fast as the AZ91D in transferring heat (temperature) from the root of the heat sink to the top of the heat sink. That is, the temperature difference between the root and top of the heat sink of the A380 material is smaller than that of the AZ91D material. This means that the air temperature at the root of the heat sink made of AZ91D material is different from the air temperature at the top of the heat sink, which is larger than that made of A380 material. Therefore, the diffusion convection of the air inside the heat sink is accelerated and the heat dissipation efficiency is improved.

3. In the actual life test situation:

3.1. Test the temperature change of ￠100mmLED lamp of the same specification made of magnesium alloy and aluminum alloy material. Methods: after heating the lamp at 200℃ for 10min, the heat source was removed, and the temperature was measured every 30sce at the indoor air temperature of 23℃. Results The cooling speed of magnesium alloy lamps was significantly higher than that of aluminum alloy lamps.

3.2. Die casting test: when die casting the same specifications of magnesium alloy and aluminum alloy materials, the die opening time of magnesium alloy materials is shortened by half than that of aluminum alloy. It shows that the heat dissipation performance of magnesium is faster than that of aluminum alloy.

3.3 Actual test compares the heating temperature of LED lamps made of magnesium alloy and aluminum alloy of the same model. Results The temperature difference between the heat sink of aluminum alloy LED lamp and the heat source was 3℃, while the temperature difference between the LED lamp made of magnesium alloy material was 5℃. The heat sink of the lamp made of magnesium alloy material is conducive to the air flow from the bottom up.