An example of four seamed CNT panels. Note: the people are for scale only. Image: Nanocomp Technologies Inc.
Technology to seam these panels into rolls of indefinite length also exists. This process facilitates handling for surface modification or for infiltration with resins on industrial equipment. The picture above shows an example of such a seamed panel. Scale-up plans from these processes envision a six metric ton capacity for sheet and yarn material by 2013.
We are planning to build a 100,000 square foot production facility that will make sheets and yarns at industrial scale product volume.
One of the biggest areas we’ve found is to replace copper wire in aerospace materials. For example, with a composite material that is 90 percent lighter than copper, aerospace structures like satellites or an aircraft like the new Boeing 787, which has 61 miles of cable, can see a drastic weight savings. We are also exploring composites for structural applications in aerospace, but this is early work with more to accomplish.
We have seen real traction in utilizing our materials on a composite as an EMI shield, especially in aerospace. This is leading to new types of composites that have several functions, such as structural strength with electrical conductivity.
Applications for these materials are broad, and leverage the following properties:
Electrical—for lightweight conductors, EMI shielding, ground plane and microwave reflectors. The excellent shielding quality of the CNT material allows it to be used as a substitute for copper braid in single or multiple conductor shielded cable. Weight savings from this step alone may range from 30 to 50 percent as compared to conventional materials used for shielding. Another application is to replace copper conductors at very high frequencies where the impedance of CNT conductive yarns can be better than copper.
Thermal—for heat straps, thermal interfaces for IC cooling and thermal interface materials. The thermal conductivity of individual tubes can be very high, exceeding 2000 W/oK at the nano-scale. Conductivity at the macro-scale, as seen in CNT sheets, is generally around 60 W/oK . However, CNT sheets have a density of 0.4 g/cc which is about 7 times better thermal conductivity than copper on a per weight basis. The material acts like a black body from near UV to 12 microns in the infrared and strips of this material can be used for Joule heaters at very high specific power.
Mechanical—for armor, composites and bonding improvements with graphite epoxy.