Aluminum substrate for automobiles is a common metal-based copper-clad laminate, which possesses good thermal conductivity, electrical insulation performance, and mechanical processing performance. The thermal conductivity of automotive aluminum substrates generally varies, such as 1.0, 1.5, 2.0, 3.0, 8.0, 122, etc. The higher the thermal conductivity, the better the heat dissipation. However, the specific situation should still be determined based on product requirements.

The thermal conductivity of automotive aluminum substrates is one of the important indicators for evaluating the quality of aluminum substrates. The other two important factors are the thermal resistance value and the withstand voltage value of the aluminum substrate.

How much is the thermal conductivity of automotive aluminum substrates generally?

The specific thermal conductivity of aluminum substrates can be measured by instruments. The level of thermal conductivity of automotive aluminum substrates directly affects their price. Generally, the higher the thermal conductivity of the automotive aluminum substrate, the relatively higher the price of the aluminum substrate.

The quality of aluminum substrates cannot be judged solely by thermal conductivity. The performance of aluminum substrates is determined comprehensively by thermal conductivity, thermal resistance value, and withstand voltage value, not by a single factor.

However, the thermal conductivity of aluminum substrates is generally fixed and does not change with external factors. The thermal conductivity is mainly determined by the raw materials of the aluminum substrate. If high thermal conductivity materials such as copper or silver are added, the thermal conductivity of the aluminum substrate material will certainly be higher. Thermal conductivity is a fundamental physical property; for a material with a fixed composition, the thermal conductivity is unrelated to its thickness or area.

Currently, materials with high thermal conductivity are typically ceramics, copper, etc. However, due to cost considerations, most products on the market are aluminum substrates. Correspondingly, the thermal conductivity of aluminum substrates is a parameter of concern. Higher thermal conductivity is one of the indicators representing better performance.

Typically, thermal conductivity refers to the amount of heat transferred through a material with a thickness of 1 meter, under steady-state heat transfer conditions, with a temperature difference of 1 degree (K or ℃) between the two surfaces, across an area of 1 square meter in 1 second. The unit is watt per meter-kelvin (W/(m·K)), where K can be replaced by ℃.

Thermal conductivity only applies to heat transfer through conduction. When other forms of heat transfer exist, such as radiation, convection, and mass transfer, the composite heat transfer relationship is generally referred to as apparent thermal conductivity, explicit thermal conductivity, or effective thermal conductivity.

Additionally, thermal conductivity is defined for homogeneous materials. In practical situations, there are also porous, multilayer, multi-structure, and anisotropic materials. The thermal conductivity obtained for such materials actually represents a comprehensive thermal performance, also known as the average thermal conductivity.