CarbAl™ Heat Transfer Material

CarbAl™ heat transfer material, recognized as one of the 100 most significant product innovations in 2009 by R&D magazine

Managing thermal issues have reached the forefront of technical impasses with respect to high powered electronics. Today, temperature control is the number one cause of failure for electronics, and results in more failures than all other contributors combined.

The CarbAl™ heat transfer material has a unique combination of low density, high thermal diffusivity, high thermal conductivity, and a low coefficient of thermal expansion (CTE) that results in a material that far exceeds the capabilities of conventional passive thermal management materials.

The technical advantages of the CarbAl™ material can be seen by comparing properties of passive thermal management materials. The speed to remove heat from a heat source or "hot spot" (i.e. thermal diffusivity) is two to three times higher than conventional materials. CarbAl™ material has a density (i.e. specific gravity) less than all the materials listed, even aluminum. The ability to remove heat energy from a heat source to its surroundings (i.e. thermal conductivity) is even higher than for copper.

   
CarbAl™ Material
Al-C400
Aluminum Silicon Carbide
Al-SiC(55)1
Aluminum

1060
Copper
Thermal diffusivity  cm2/sec 2.33-2.78 0.86 0.84
1.1
Thermal conductivity W/mK 370-488 200 204
390
Coefficient of thermal expansion  1/K 7*10-6 10*10-6 24*10-6
17*10-6
Electric resistivity μΩ•cm 4.0 20.7 2.8
1.7
Specific Heat J/gK 0.75 0.786 0.9
0.4
Specific Gravity g/cm3 2.1 2.96 2.7
8.9
Bending strength MPa 40 450 80
350
Young's Modulus GPa 12 167 70
119
1CPS Technologies 

A major technical advantage of CarbAl™ material is its coefficient of thermal expansion (CTE) matching to materials used within the semiconductor industry. A common metric of comparison is to plot CTE versus thermal conductivity. The chart below is normalized to silicon (Si=1), the most common semiconductor material, represented by green. GaAs and GaN, other semiconductors are also noted in green. Points in blue are other materials used in thermal management. Note the most common materials, Cu and Al, have CTEs that are far from matching semiconducting materials. The only materials with a thermal conductivity higher and closer CTE than the CarbAl™ material are the ever exotic and expensive synthetic diamond films, diamond composites and HOPGs.

The carbon-based nanocomposite is comprised of 80% carbonaceous matrix and a dispersed metal component of 20% aluminum with an additive that enhances phonon coupling and inhibits the formation of aluminum carbide. Without the additive, the material would be insulating and would not achieve the thermal diffusivity and thermal conductivity that contributed to CarbAl™ material's award winning status.

The CarbAl™ material currently being produced, offers two times the thermal conductivity in one plane as compared to the thermal conductivity in the other two planes. This results in a material that is extremely useful in removing heat created by high watt density applications. This feature is unlike that of both lower thermally conductive materials and higher thermally conductive materials which are highly anisotropic such as highly ordered graphite (HOPG) and graphite felts.

CarbAl™ material is produced in rectangular blocks of approximately 140mm X 190mm X 240mm with the greatest thermal conductivity in the thickness. It can be provided with the dimensions and shape needed for a specific application or as a large block for those customers with machining capabilities.

Contact Applied Nanotech, Inc. for a solution to your thermal management needs

Please contact Applied Nanotech, Inc., sales(at)appliednanotech.net to discuss your thermal management requirements. If you would like to improve your product reliability and decrease problems caused by temperature issues and thermal stress for applications such as IGBT, lasers, CPV, ICs, video cards, high power LEDs, electronic packaging and optoelectronics, CarbAl™ heat transfer material may be the solution.

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