SBIR Funding Furthers DexMat CNT Technology

Source: Original article appears in the December 2018 issue of the Wire Journal International.
The feature on DexMat is on pages 48-50.

DexMat CNT Tape as Lightweight EMI Shielding

In this video we explain how DexMat’s carbon nanotube (CNT) tape has been used to replace the two EMI copper shielding braids typically used in RG316 cables. The performance of DexMat prototypes matches standard RG316 performance, while reducing the total weight of the cable by 50%!

The shielding effectiveness and insertion loss results for the CNT and Cu shielded cables are shown below. The CNT tape shielded cables have the following advantages:

  • Overall RG-316 cable weight reduction of CNT shielded vs. Cu double braid shielded cable without connectors is over 50%
  • CNT tape shield is 100 microns thick compared to 500 micron thick Cu double braid shield
  • Easy to apply CNT tape to coaxial as well as twisted pair type cables
  • Wide range of CNT tape widths and lengths are available for purchase
  • CNT tape shielded cables survive at least 1000 flex cycles with a minimum bend radius of at least 7.5X the jacketed cable diameter

Source: https://dexmat.com/cnt-products/cnt-tape-film/

Specification Sheet: DexMat fiber, tape, and cable specs Dec-2018

DexMat CNT Tape Shielded Cables Offer 50% Weight Reduction

Houston, TX- 12/11/2018. Working in collaboration with Minnesota Wire & Cable Company, DexMat has produced carbon nanotube (CNT) tape shielded RG-316 cables that perform comparably to copper (Cu) double braid shielded RG-316 cables. However, the CNT tape shields are 95% lighter than the copper double braid shields. The shielding effectiveness and insertion loss results for the CNT and Cu shielded cables are shown below. The CNT tape shielded cables have the following advantages:

  • Overall RG-316 cable weight reduction of CNT shielded vs. Cu double braid shielded cable without connectors is over 50%
  • CNT tape shield is 100 microns thick compared to 500 micron thick Cu double braid shield
  • Easy to apply CNT tape to coaxial as well as twisted pair type cables
  • Wide range of CNT tape widths and lengths are available for purchase
  • CNT tape shielded cables survive at least 1000 flex cycles with a minimum bend radius of at least 7.5X the jacketed cable diameter

Source: https://dexmat.com/cnt-products/cnt-tape-film/

Specification Sheet: DexMat fiber, tape, and cable specs Dec-2018

DexMat SpaceCom 5 Minute Pitch

November 28, 2018. Out of the original 17 semi-finalists, DexMat was selected as one of 5 finalists to pitch at the 2018 SpaceCom Entrepreneur Summit in Houston, TX, for the opportunity to win the $100,000 Entrepreneur Challenge. As a runner-up, DexMat won $20,000 in Google Cloud Credits.

Click here for more information on the SpaceCom Entrepreneur Summit.

DexMat Named as SpaceCom Entrepreneur Challenge Semi-Finalist

HOUSTON – SpaceCom – The Space Commerce Conference and Exposition, where NASA, aerospace and industry come together to connect, announces the finalists of the SpaceCom Entrepreneur Challenge. Taking place at the George R. Brown Convention Center in Houston November 27-28, this challenge is the culmination of the SpaceCom Entrepreneur Summit (SES). The Entrepreneur Challenge began with 56 startup applicants. Through the first round of judging, that number was narrowed to 23 and now 17 semi-finalists who will present during the first day of the SpaceCom Entrepreneur Summit, Tuesday, November 27.

The semi-finalists include:

  • Arlula
  • Benchmark Space Systems
  • Cemvita Factory Inc.
  • Devali Inc
  • DexMat, Inc. 
  • EXOS Aerospace Systems & Technologies
  • Finsophy Inc.
  • Hedy-Anthiel Space Systems
  • Lazarus 3D Inc.,
  • Lucid Drone Technologies, Inc.
  • LunaSonde, LLC
  • Molon Labe LLC
  • SaraniaSat Inc.,
  • Solstar Space Company
  • STARK Industries LLC
  • Sugarhouse Aerospace
  • Swift Data LLC

At the culmination of day one, five finalists will be selected to present during a pitch competition. The winner will then be selected after the final round of pitches during the general session November 28 at 1:30 PM. During this presentation, members of the audience and a panel of judges will select the grand prize winner. These finalists are eligible to win the below prizes provided by Google Cloud for Startups:

  •  $100,000 in Google Cloud credits to the competition winner
  • $20,000 in Google Cloud credits for runners up
  • $3,000 in Google Cloud credits for every qualified entrant in the competition

Additional prizes include:

  • Guaranteed extended meeting with an investment firm
  • Speaking role at SpaceCom 2019
  • A booth at SpaceCom 2019

Source: https://spacecomexpo.com/wp-content/uploads/2018/11/SES-Finalists-Press-Release.final_.pdf

DexMat Featured in Wire Journal International

Source: Original article appears in the October 2018 issue of the Wire Journal International.
Free subscription is required to read the digital version of the article. The feature on DexMat is on pages 52-53.

Space Dust Repelling Carbon Nanotube Fibers

Abstract: The above video demonstrates how carbon nanotube fibers are integrated into a spacesuit to help spacesuits mitigate dust contamination for future lunar and Mars missions.The spacesuit fabrication and testing was performed by researchers from the University of North Dakota, Boeing, and the NASA Glenn Research Center. CNT fibers were produced by DexMat.

Spacesuit dust mitigation has been a topic of high relevance and a critical path for future planetary exploration missions including Moon, Mars and Asteroids. A previous study demonstrated utilizing Carbon Nanotube (CNT) yarns as electrodes embedded into coupons made of spacesuit outer-layer material. When a multiphase Alternating Current (AC) voltage signal was applied to this material, the spacesuit fabric repelled greater than 80% lunar dust simulant with particle sizes between 10-75m in ambient conditions. As a continuation to this study, the feasibility of scaling the CNT embedded dust removal system on larger portions of spacesuit is investigated. A scaled prototype, representative of the knee joint section of a planetary spacesuit utilizing specifics of the NDX-2 lunar spacesuit developed by University of North Dakota was constructed. The outer-layer of this prototype is embedded with the CNT dust removal system and tested under various conditions. Fabrication of this system and results from the experiments using lunar dust simulant are detailed in this paper.

Source: Spacesuit Integrated Carbon Nanotube Dust Removal System: A Scaled Prototype

DexMat Awarded Phase I SBIR: Robust Lightweight CNT Wiring for Space Systems


Abstract: 
NASA is challenged to find ways of effectively shielding sensitive electronic equipment from electromagnetic interference (EMI) without adding significant weight to space flight vehicles and satellites (the heavier they are the more fuel they need to achieve orbit).  EMI shielding for wire and cables is an attractive opportunity for weight reduction. However, with the advent of highly reusable next generation space vehicles, wiring must be not only light weight, but also strong and robust, capable of withstanding extreme conditions, intense vibration and long lifecycles. It is important that wire weight reductions do not come at the expense of mechanical strength or EMI shielding effectiveness.  DexMat is developing a novel and highly conductive Carbon nanotube (CNT) EMI shield product that will allow for significant weight reduction without compromising mechanical strength or shield effectiveness. CNTs are advancing as the most promising solution for reducing the weight of spacecraft wires.  The shielding effectiveness of CNT materials is comparable to that of heavy metal braids, but at a fraction of the weight.  Compared to a copper wire with the same diameter, a CNT fiber has 6 times higher strength, more than 6 times lower density,  and at least 25 times higher flexure tolerance, essential qualities for conductors in aerospace applications. Under this Phase I project, DexMat will develop CNT shielding braid (made from CNT yarn from Dexmat) that can potentially increase the mechanical strength of CNT tape used as a primary EMI shield. These CNT braids will be of different thicknesses and area coverage, to augment the performance and product appeal of CNT tapes. Additionally, DexMat will begin to conduct the first accelerated aging tests to determine the impact on mechanical strength of shielding made with CNT tapes, CNT yard braids, and hybrid CNT tape/braid combinations.

Potential NASA Applications: 
The first planned product to contain DexMat technology is lightweight CNT cables. CNT cables combine high strength, electrical and thermal conductivity with low density, making them ideal for aerospace applications where weight reduction is a priority, including reusable next generation space vehicles and satellites. Given the tremendous costs associated with satellite launches, NASA and the aerospace industry will see substantial savings from our CNT-based wire.

Potential Non-NASA Applications: 
DexMat CNT technology has applications in the military aircraft and commercial aviation markets, to effectively reduce weight of aircraft and satellite designs.  For a single-aisle aircraft, a 1% reduction of in weight can lead to a net cost savings of $240K-$1.6M per year in use. For larger aircraft, the savings can reach $2.4-5M. Additional applications include wearable electronics, eTextiles and bioelectronics.

Carbon Nanotubes Could Provide the Military With Battery-Power in Textiles

Carbon Nanotubes Could Provide the Military With Battery-Power in Textiles

The carbon fibers can be spooled into strong, conductive thread. Like spider silk, it is stretchy and strong. Credit: Joseph Fuqua II/UC Creative Services
Carbon nanotubes could lead to clothing that can double as a battery, a discovery that could be particularly useful for the military.

A team from the University of Cincinnati—in a partnership with the Wright-Patterson Air force base—are working to take advantage of the properties of carbon nanotubes in developing new applications for soldiers in the field.

“The major challenge is translating these beautiful properties to take advantage of their strength, conductivity and heat resistance,” UC professor Vesselin Shanov, who co-directs UC’s Nanoworld Laboratories, said in a statement.

Graduate student Mark Haase has worked with Air Force researchers over the past year to find applications for carbon nanotubes using X-ray computer tomography to analyze samples.

“This pushes us to work in groups and to specialize,” Haase said in a statement. “These are the same dynamics we see in corporate research and industry. Engineering is a group activity these days so we can take advantage of that.”

The researchers used chemical vapor deposition to grow the carbon nanotubes on silicon wafers the size of a quarter under heat in a vacuum chamber.

“Each particle has a nucleation point,” Haase said. “Colloquially, we can call it a seed. Our carbon-containing gas is introduced into the reactor. When the carbon gas interacts with our ‘seed,’ it breaks down and re-forms on the surface. We let it grow until it reaches the size we want.”

UC’s Nanoworld Lab set a world record in 2007 by growing a nanotube that stretched nearly two centimeters, the longest carbon nanotube array produced in a lab at the time. The lab can currently create nanotubes that are substantially longer.

They were able to stretch the little fibrous square over an industrial spool in the lab to convert the sheet of carbon to a spun thread that can be woven into textiles.

“It’s exactly like a textile,” Shanov said. “We can assemble them like a machine thread and use them in applications ranging from sensors to track heavy metals in water or energy storage devices, including super capacitors and batteries.”

This ultimately could lead to a much lighter load for soldiers in battle.

“As much as one-third of the weight they carry is just batteries to power all of their equipment,” Haase said. “So even if we can shave a little off that, it’s a big advantage for them in the field.”

The study was published in Materials Research Express.
Full article by Kenny Walter – Digital Reporter @RandMagazine here.

Mil-Aero Industries Eye Carbon Nanotubes as They Target Cost Savings

Ultra-lightweight carbon nanotubes may replace copper wires.

Today’s aerospace and aircraft industries focus on size, weight, power, and cost (SWaP-C), and cost is now often figured for program or operational life, which may total thousands of dollars per pound. This gives tremendous impetus and justification to accept high-cost new technology to obtain weight savings.

Reducing F-35 by 20 Pounds Could Provide $230M Savings

Satellites have always paid extra to reduce weight since each payload pound may cost more than $5,000 to launch. Studies by the Center for Strategic and Budgetary Assessments (CSBA) show that the new F-35 has a $4,500 cost per pound over the aircraft’s operational program life

until 2070. (For comparison, the cost per pound for the F-22 is estimated at $3,500.) The F-35 has projected production of2,557 aircraft for the U.S. and nine for export customers scheduled through 2037. Therefore, a weight reduction of just 20lbs per plane could result in savings of $230,000,000! Even if this is off by 50%, the expected benefits already are driving new industry developments.

In addition to fighter aircraft, each ounce is also critical in future soldier wearables, UAVs, portable radars, vehicle communications, and other equipment to increase survivability, mission endurance, and success.

Interconnect weight savings are being obtained by incorporating higher contact density, composite materials, combinational multi-port connectors, and other approaches. However, a new technology involving carbon nanotubes (CNTs) is emerging and offers a lightweight alternative to copper wire and other conductive shielding materials. A carbon nanotube is produced as a layer of carbon atoms in a tubular configuration, in single- or multiple-walled versions.

CNTs are being mixed with polymers to create high-strength, lightweight composite materials. CNT fibers can be made into conductive sheets and tapes, which offer a myriad of potentials. Optimal performance may result from spinning CNT fibers into conductive threads (referred to as yarn) to potentially replace copper wires in harnesses, motor windings, and shields.

Another important gain is reliability. CNT fibers and yarn can withstand millions of bending cycles, while standard fiber/wire would have yielded many times. The minimum bending radius requirements of today’s cable is not applicable for CNT fibers and cables.

Market potentials for CNT technology are bringing new companies into the forefront. Nanocomp Technologies offers commercial CNT fibers created using a carbon vapor deposition (CVD) reactor and then formed into sheets or fibers that can be twisted into shields or primary conductors. Another supplier is Syscom Advanced Materials Inc., which provides a variety of metal-clad fibers.

DexMat Inc. in Houston produces CNT fiber using a wet acid process that draws multiple fibers that can be shaped into a shield or primary conductor, and future developments for  include flat tape. The company boasts a strong Ph.D. cadre from nearby Rice University where they have successfully fabricated coaxial cable inner and outer conductors by coating a solution of CNTs in chlorosulfonic acid to achieve a two-times better conductivity than seen previously. This may prove an attractive alternative to commercial coax cable using tin-coated-copper with comparable attenuation and greater mechanical durability with 97% reduced mass, according to the company.

Usually, the outer conductor is the heaviest portion of today’s cables. In coax, the outer conductor provides both signal transmission and electromagnetic shielding. While shielding does not require high conductivity in the outer conductor, signal loss (i.e., signal attenuation) through the transmission line is significantly affected by the conductivity and architecture of the outer conductor. The new solution-coated CNT outer conductors offer near-term application potentials. Several connector companies are reportedly studying termination techniques.

Carbon Nanotube Materials Provide Shielding

TE Connectivity has been working to use CNT materials for shielding and data transmission cables. In a paper presented at the 2012 IWCS Conference, Dr. Stefanie Harvey, senior manager for corporate strategy, reported that they had achieved greater than 50dB shielding effectiveness in the GHz range, and their “data transmission cables using a yarn format perform comparably to MIL-STD-1553.” In the January 5, 2016 issue of ASSEMBLY, Dr. Harvey reviewed how replacing the braid in RG-58 cable would reduce weight from 38.8 grams per meter (g/m) to 11.5g/m, while replacing the center conductor with CNT yarn would further reduce weight to 7.3g/m for a combined weight reduction of 80%.

Composites are used to replace heavy copper wire with metal plated aramid fibers for use in wire and cable EMI shielding. EMI shielding made with plated aramid fibers can reduce weight by as much as 80%, leading to major weight reduction depending on the size of the aircraft or satellite. Aramid fibers are a class of strong, heat-resistant synthetic fibers, the best known of which is DuPont™ Kevlar®, used in ballistic-rated body armor.

Carlisle Interconnect Technologies (formerly Micro-Coax Inc.) provides a unique weight-reducing EMI/RFI shielding solution using their proprietary high-strength ARACON® brand metal clad fibers. Ron Souders, technical director, Carlisle Interconnect Technologies, advises that, for typical applications, switching to ARACON allows a weight savings of 80% when compared to traditional metal braided or woven EMI shielding products. This offers the conductivity of an outer metal coating with the strength, light weight, and flexibility of aramid fiber.

*Note: DexMat also provides products for shielding applications not mentioned in this article.

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Ron Souders further explained that the specific gravity of aramid fiber is only 1.44g/cc, compared to copper at 8.9g/cc, and that, even with the addition of metal coatings, the specific gravity of ARACON fibers ranges from 3 – 5g/cc. The tensile strength (measured in kilopounds per square inch, or Ksi) of the aramid core (350Ksi) is from three to 10 times higher than that of traditional or high-strength copper cores, which typically span 35 to 95Ksi. Since ARACON fibers behave like a textile, they are far more flexible and compliant than metal.

Industry Standardization is Underway

The benefits offered by CNT fiber, whether as EMI/RFI shielding, signal or coaxial cable, or other new components, have prompted the Naval Air Systems Command (NAVAIR) in Patuxent River, Maryland, to sponsor the establishment of suitable “Military Specification for Conductive Carbon Conductors used in Aircraft Wiring,” eventually with QPL sources. The proposed formal qualification program should stabilize components and materials for future use.

CNT technology also was included in a recent multiple-day RF coordination meeting held in February by the Defense Logistics Agency (DLA) at the Defense Supply Center Columbus (DSCC). Suppliers of basic CNT materials, wire, cables, cable assembles, and signal and RF/microwave connectors are now working on both application-specific and generalized products to achieve the weight reduction and reliability benefits offered by CNT and other metallized fibers.

Original story by David Shaff – April 28, 2017