The scientists developed a heat-spreader that consists of a copper-graphene composite that was attached to an "electronic device" with an indium-graphene interface film. Tests showed that the increased conductivity by using graphene can dissipate heat about 25 percent faster than pure copper. Kasichainula also noted that graphene is less expensive than pure copper, which could reduce the cost of heat spreaders in the future.
In a paper published in the April 2012 issue of Metallurgical and Materials Transactions B claims the researcher describes test results in which a 200 micron thin film of copper-graphene deliver a thermal conductivity of 460 watts per meter per kelvin (W/mK), up from just 380 W/mK of electrolytic copper at a temperature of 27 degrees Celsius. The conductivity of copper-graphene increases with lower temperatures and decreases with substantially higher temperatures. Kasichainula said that the conductivity was 510 W/mK at -23 degrees Celsius and 440 W/mK at 77 degrees Celsius.