How to choose the correct thermal conductivity interface material
More and more electrical designers are facing the challenges of equipment shape or heat dissipation, but they may not be familiar with the selection range of heat conduction interface materials in the market, nor how to select the correct material mix to solve specific design challenges. Du Bonlaird High Performance Materials Department provides a variety of heat conduction interface material options, which can help designers solve complex heat conduction challenges. These solutions are applicable to automobiles, telecommunications, data centers, power conversion systems, and many other products.
The thermal conductive interface material is intended to provide a uniform thermal contact surface for two mating surfaces, especially between elements and their radiator mating surfaces. In the past, system designers usually used fans and/or radiators as a panacea for solving most cooling problems on specific elements. This is because most heat is generated in large power supplies or large CPUs, Both are large enough to accommodate this kind of cooling equipment. Even in the new generation of systems through which forced air flows, there is still a problem of how to quickly dissipate heat from the components to the radiator. The heat conduction interface material provides a heat conduction solution by filling the gap between the machined surfaces to ensure uniform contact and high heat transfer efficiency. The same method is also applicable to the case where the shell is used as a heatsink.
Types of thermal conductive interface materials and compounds:
Liquid dispensing caulking materials, which are more commonly known as Thermal paste, thermal gel or thermal grease. These materials can be directly applied to components as adhesives for radiators; Due to the difficulty of reprocessing, they are rarely used as interface materials for shells. These materials can be mixed with ceramic fillers, metal or metal oxide fillers to achieve high thermal conductivity.
Thermal Grease and phase change material; Thermal grease can be obtained by using a screen printing solution to obtain a smaller adhesive layer thickness. Phase change grease is a more advanced alternative to thermal grease, and through optimization, the maximum heat transfer rate can be achieved within a specific temperature range. These materials are usually used for radiators that are fixed by mechanical force and fixed in place under constant pressure. During operation, phase change materials solidify or liquefy into a viscous layer, releasing or absorbing latent heat separately, These high adhesive layer materials can be printed using screen printing to obtain the minimum adhesive layer thickness.
Thermal Pad: These preformed solid materials are very simple to use, and can also be integrated into the automatic assembly process. Although the Thermally conductive pad generally adopts the preformed shape, it can also be die-cutting according to the required size. They are suitable for use on planar elements to connect the radiator, or directly attached to the shell.
There are a variety of material specifications applicable to thermal conductive interface materials. The thermal conductivity of materials or the thermal resistance of products provided are the main material properties to be considered, because this value can be used as a design goal in simulation or some basic calculations. In addition to material characteristics, designers should also consider the automated assembly process in the manufacturing process, as well as the production convenience of integrating specific solutions into PCBA or housing.
