Engineers question: The key to the quality of LED lamps lies in good heat dissipation?

The stability and quality of LED lights are closely related to the heat dissipation of the lamp body. Currently, the heat dissipation of high-brightness LED lights on the market usually adopts natural heat dissipation, which is not ideal. If the heat dissipation is not ideal, the life of the lamp itself will also be affected.

The industry should not only focus on the heat dissipation coefficient and ignore the thermal resistance value when applying heat dissipation materials. If you only see that a certain heat dissipation patch, heat dissipation paste, heat dissipation paint or thermal conductive film has a good heat dissipation coefficient and think that it can conduct away high heat, you may be greatly disappointed. The expected temperature will drop, the LED epitaxy will not decay due to overheating, the life of the street lamp can be effectively extended, and the acceptance will pass smoothly, which may not happen.

From etching the circuit board with tin, coating the LED backlight ink, applying the protective film and baking in the oven, leveling the whole board, pasting the thermal conductive film, and then combining the heat dissipation module with adhesive or locks, it can be found in this tedious process that no matter how good the thermal conductivity of the material is, it will be defeated by the thermal resistance impedance. Air, loose pores at the joints, heat dissipation gaskets, powder formed after the volatilization of the silicone oil in the heat dissipation paste, and the thickness of the multi-layer thermal conductive film will all form thermal impedance. These multi-layer thermal resistances will hinder the heat conduction rate, and the heat conduction is very slow, and it may not even be conducted to the surface of the lamp, resulting in the continuous accumulation of heat. The white backlight ink on the surface of the aluminum substrate must not only be able to reflect, but also be able to dissipate the heat of the lower layer through the backlight ink on the surface.

Some manufacturers are not careful and use ordinary white text ink instead of LED-specific backlight ink, which is equivalent to adding a layer of hard paint to seal the heat. After many failures, some manufacturers have accepted new concepts and processes, focusing on the overall heat dissipation solution. The aluminum substrate is replaced with LED-specific heat dissipation type white backlight ink coating. If a slightly yellow backlight ink is specified, the reflectivity will be increased to 91%. Spraying soft ceramic heat dissipation paint between the copper foil substrate and the aluminum substrate can reduce the use of Japanese thermal conductive adhesive film and increase the breakdown voltage at a very low cost.

To protect the lamps from the erosion of the climate environment and effectively conduct the heat away, a cost-effective and effective method is to spray soft ceramic heat dissipation paint. Only by starting from the overall heat dissipation concept and reducing the interference of thermal resistance can the key to the acceptance of large LED lamps pass. The protective shell of the lamp should abandon the traditional electroplating or baking paint, which will seal the heat back into the lamp.