Nanotechnology is dramatically changing the way that numerous products are manufactured. It allows engineers to create new materials that are lighter and stronger than traditional alternatives.
The aerospace industry is cutting edge in many applications, but it has often been slow to adopt new wire processing technology. However, Nanocomp Technologies Inc. hopes to change that. The company is working with the U.S. Air Force to develop wiring and shielding panels from carbon nanotubes.
Carbon nanotubes (CNTs) have a strength-to-weight ratio that is not matched by any other known material. Nanocomp engineers have figured out how to turn them into material that has very high tensile strength, highly efficient electrical conductivity, electromagnetic interference (EMI) shielding capabilities and extreme light weight.
The six-year-old Concord, NH, company has been awarded a research contract to develop nanotechnology-based products for use in the aerospace industry. “This funding [will be used] to advance the suitability of nanotube-based material for a number of aerospace applications, ranging from thermal management and electromagnetic shielding to electrical and power generation system enhancements,” says Peter Antoinette, president and CEO of Nanocomp.
“The light weight and conductive nature of CNTs make them extremely attractive for many aerospace applications,” explains Antoinette. “To date, however, most development activities have taken place on a small scale with ineffective results due to performance, production and cost limitations. As a result, integrating CNT macrostructures into large-scale trials has not yet been achieved. Nanocomp’s materials and production capabilities leave these barriers behind.”
During a Phase I contract several years ago, Nanocomp successfully demonstrated the use of lightweight conductive wires made from CNTs. During Phase II, “[we are] are optimizing processing and manufacturing methods to produce CNT wiring in the quantities and forms required for direct integration into aircraft electric power applications,” says Antoinette.
The Air Force awarded Nanocomp the second small business innovation research contract to develop carbon nanotube mats as a viable substitute for nickel-based conductors in electrostatic discharge (ESD) and EMI shielding applications. The goals of this program are to optimize the properties of CNT sheet materials to meet shielding requirements, develop a process to integrate the mats into existing commercial EMI-ESD shielding systems, and develop on-line production and quality-control methods.
“The nature and importance of these projects demonstrates the unique potential of our material as the basis for creating game-changing, yet cost-effective replacements for traditional aerospace components,” Antoinette points out. “We’ve proven that the performance of CNT wiring is superior to that of copper for high frequency applications, with dramatic weight savings.
“The critical next [phase] of moving to commercialization is optimizing our manufacturing process for wire and cable applications,” adds Antoinette. “We look forward to successfully demonstrating an ultra lightweight CNT-based solution for ESD and EMI shielding.”
According to Antoinette, carbon nanotube sheet and yarn materials, which come wound on spools like traditional wire, provide an excellent way to solve novel wiring challenges in the aerospace industry, particularly where weight and payload are concerned, such as unmanned air vehicles.
Antoinette says there are five primary benefits of using CNT material for wiring harness applications:
- Significant weight savings—25 percent to 50 percent in total cable weight, depending on cable type and replacement strategy.
- Durability—CNT materials are inherently resilient to corrosion and mechanical stresses; much more so that conventional metals.
- Naturally conductive—allows for a number of electrical applications to thrive simultaneously. such as shielding, lightning protection, wiring or any combination of these.
- Low insertion risk for many applications.
“[Our] CNT materials are significantly lighter than traditional copper wiring technology,” claims Antoinette. “[The material weighs only] 0.4 grams per cubic centimeter, as compared to copper, which is nearly 9 grams per cubic centimeter. In addition, especially at higher frequencies, CNT wiring exhibits comparable or better conductivity than conventional copper.”
However, there are several challenges to using nanotechnology for wiring applications. “There two primary challenges: Achieving comparable electrical performance at lower frequencies and meeting the material capacity demands of wiring at full scale,” says Antoinette.
Despite those issues, Antoinette predicts that nanotechnology will be key to future aerospace wiring applications. “The feedback we are receiving indicates that CNT technology is going to play a major role, even in the case of certain existing platforms,” he explains. “This view is being expressed by the contractor community, as well as end users, who clearly see the weight savings and environmental friendliness of CNT materials.”