The thermal conductivity of led substrate is related to the insulation layer (usually PP, thermal grease, etc.) inside the aluminum substrate, and it is one of the three criteria to measure the quality of aluminum substrate (thermal resistance and withstand voltage are the other two properties). The thermal conductivity of aluminum substrates can be measured by testing instruments after the plates are pressed together. Ceramics and copper are usually the ones with high thermal conductivity. However, due to the cost, electronic aluminum substrates are the mainstream in the market, and the corresponding thermal conductivity of aluminum substrates is a parameter that everyone pays attention to. The higher the thermal conductivity, the better the performance.
The thermal conductivity of aluminum substrate is usually divided into three coefficients, namely, zero, zero, and so on, that is, the average, medium and high thermal conductivity, which is mainly determined by the insulating layer of aluminum substrate.
Factors affecting thermal conductivity of led aluminum substrate
Thermal conductivity refers to the compound heat transfer relationship when there are other heat transfer forms, such as radiation, convection and mass transfer. This property is usually called apparent thermal conductivity, explicit thermal conductivity or effective thermal conductivity.
In addition, the thermal conductivity is for homogeneous materials. Actually, there are porous, multi-layered, multi-structured and anisotropic materials. The thermal conductivity obtained by this material is actually a comprehensive performance of thermal conductivity.
At present, many people in LED aluminum substrate market care about the thermal conductivity of aluminum substrate. Although the thermal conductivity of aluminum substrate is very important, it is not the only reference standard. In the market, the thermal conductivity of single-layer aluminum substrate is usually PP insulation layer, which is used by most aluminum substrate manufacturers. The better thermal conductivity is that the insulation layer is thermal grease, which is the key material composition.
Actually, the thermal conductivity of led aluminum substrate mainly depends on the thermal conductivity of the middle insulation layer. The smaller the thermal resistance, the faster the thermal conductivity and the better the heat dissipation.