How to improve the heat dissipation effect of LED explosion-proof lamp
LED explosion-proof lamp radiator naturally chooses metal as the material of the radiator. For the selected material, I hope it has both high specific heat and high thermal conductivity. From the above, it can be seen that silver and copper are the best thermally conductive materials, followed by gold and aluminum, but gold and silver are too expensive, so, At present, the heat sink is mainly made of aluminum and copper. In comparison, both copper and aluminum alloy have their own advantages and disadvantages: copper has good thermal conductivity, but the price is more expensive, the processing difficulty is higher, the weight is too large, and the heat capacity of the copper radiator is small and it is easy to oxidize .
On the other hand, pure aluminum is too soft to be used directly. All aluminum alloys are used to provide sufficient hardness. The advantages of aluminum alloys are low price and light weight, but the thermal conductivity is much worse than copper. In order to strengthen the heat dissipation of the LED explosion-proof lamp, the past FR4 printed circuit board has been unable to cope with it, so a printed circuit board with a metal core, called MCPCB, is proposed. Accelerated heat dissipation, but due to the characteristics of the insulating layer, its heat conduction is subject to several restrictions. For light, the substrate must be transparent enough so that it does not hinder the light, or a reflective material layer is added between the light-emitting layer and the substrate to avoid light energy being hindered and absorbed by the substrate, resulting in waste, in addition The substrate material must also have good thermal conductivity, which is responsible for quickly dissipating the heat released by the die to the lower heat sink, but an interface with good thermal conductivity must also be used between the substrate and the heat sink, such as solder or Thermal paste. At the same time, the epoxy resin or silicon resin (sealing layer) above the die must also have a certain heat resistance, for the temperature from the p-n junction to the surface of the die must be conducted. In addition to strengthening the substrate, another method is flip chip inlay, which turns the bare crystal electrode above the LED explosion-proof lamp to the bottom. The electrode is directly connected to the lower bottom wire foil, so the heat can be transferred to the bottom faster. This kind of heat dissipation method is not only used on LEDs, but nowadays high-heat CPUs and GPUs have also implemented this method to accelerate heat dissipation.
