Custom and Standard Model (X-Series®) Links
PGL™ and GTL™ products are made entirely of NASA approved, low/zero outgassing materials, and are provided in standard and custom configurations. X-Series® Links/Straps are our standard model line, and can be manufactured with either PGS or Graphene Foil (depending on customer preference and performance requirements). The X-Series® is comprised of 6 standard models, with multiple end fitting options (at no additional cost). To learn more about our standard and custom strap offerings, request the X-Series® Catalog.
X-Series®
- Available in 3 Fixed Widths
- Available in 2 Thicknesses
- Available with PGS or Graphene Foil
- 6 Models to Choose From
- 2 Semi-Customizable End Fitting Types Available
- Length Customizable
- Bolt Pattern Customizable
- No NRE or Design Fees
- Thermal Test(s) - OPTIONAL
- End Fitting Chromate / Passivation - OPTIONAL
- Typical 7-8 Week Lead Times
Pictured: X6-501 PGL™ with dual aluminum L-fittings. |
Custom PGL™ & GTL™
- Available in Nearly any Width
- Available in Nearly any Thickness
- Available with PGS or Graphene Foil
- End Fitting Material Customizable
- Fully-Customizable End Fittings
- Length Customizable
- Bolt Pattern Customizable
- Prototype/Protoflight Program Required
- Thermal Test(s) - INCLUDED
- End Fitting Chromate / Passivation - OPTIONAL
- Typical 8-9 Week Lead Times
Pictured: Custom PGL™ with dual flat aluminum fittings.
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Superior Thermal Performance
TAI's PGL™ and GTL™ products offer the highest thermal performance available in the industry; providing a material thermal conductivity of 1,600- 2,500 W/(m-K), depending on material, operating temperature, and sheet thickness (though graphene sheets may one day offer even higher thermal performance than the current 1,840 W/(m-K) available in the industry, as the technology improves). However, the materials used are just one aspect that makes our products unique. These materials, when combined with our proprietary design and assembly methods (which minimize resistance losses), result in unrivaled thermal performance.
Though these straps do not have years of space qualification and flight heritage (like our copper and graphite fiber thermal straps), they are a unique product, offering a particular set of benefits which make them ideal in volume-restricted applications like Xilinx™ electronics boxes, FPGA/chip & PCB cooling applications, and cubesats.
*It should be noted that we do not provide "monolayer graphene straps," as there are no (actual) monolayer graphene sheet thermal straps available in the industry. While a single layer of graphene can achieve conductivity in excess of 3,500 W/(m-K), it is only 0.35 nm thick.
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Pictured: GTL™, 1.0" x 3.0", Conductance = 0.86 W/K (March 2018).
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Pictured: PGL™, 1.0" x 3.0", Conductance = 0.70 W/K (March 2018).
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Pictured: GTL™ pre-thermal conductance test (March 2018).
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Pictured: PGL™ pre-thermal conductance test (March 2018).
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Important Note on Material Thermal Conductivity: the values in the graph represent the conductivity of the various ("flexible portion") materials used in thermal straps, at different temperatures. They are not necessarily indicative of the measured performance of a thermal strap assembly (i.e., a GFTS®, GTL™, or PGL™ strap assembly will not guarantee 2X - 4X the performance of an equivalent-sized copper cable or foil configuration). This is because metallic straps are more densely packaged, and there are resistance losses associated with the assembly processes (epoxying and clamping), and via stacking sheets or adding additional ropes and/or rows. For performance projections of any of our strap products, please contact us at any time. Our front end design and assessment services are complimentary, and can save you the trouble of attempting your own conductance calculations.
Pyrolytic Graphite Sheet (PGS) vs. TAI's Graphene Foil
Though our team has manufactured PGL™ products using multiple PGS materials & sheet thicknesses, the most common is our laboratory-verified, 1,600 W/(m-K) sheet. At 1,840 W/(m-K), our Graphene Foil offers the industry's highest strap material thermal conductivity—but there are trade-offs to consider...
Determining which material is best-suited to your application is dependent upon your thermal and mechanical requirements. While Graphene Foil offers slightly higher performance than PGS (on the assembly level), a strap made with PGS is more flexible, and less prone to stress fractures and kinks when sheets are flexed. Further, the thermal conductivity of TAI's PGL™ products peaks near 150K, making them better-suited for lower temperature applications (60 - 200K), than Graphene Foils/Sheets (which peak at 220K).
Pictured (Top): PGL™ manufactured by TAI (November 2014).
Which Carbon-Based Thermal Strap/Link is Right for Me?
TAI offers multiple carbon-based strap products because no single configuration or material is ideal under all operational and environmental conditions.
Though they have a lower thermal performance, our Graphite Fiber-based straps are more durable and lighter than carbon sheet straps, and they can be flexed on the lateral axis/provide lateral deflection (which is helpful for applications such as battery pack cooling, antenna arrays, optical instruments, and some deployable/moving/rotating instruments and equipment). Though spaceflight customers most commonly choose GraFlex I and II, GraFlex III is also ideal for applications with extremely limited volumes, but requiring flexibility on each axis. GraFlex rope and woven sheet material is also less expensive than PGS and Graphene Foils, as are GFTS™ assembly costs.
Carbon foil/sheet straps offer superior thermal performance, but at the cost of durability and lateral flexibility/deflection. These straps are better-suited to applications with compact envelopes, requiring little to no flexibility/range of motion or repeated flex cycles (such as electronics boxes, chip cooling, etc.). Because of their higher performance at lower temperatures, PGL™ products are now a superior replacement for aluminum foil thermal links at temperatures as low as 50K, and can be used in place of OFHC copper straps at temperatures as low as 70 - 80K (to reduce mass but offer similar thermal performance).
Pictured (Right): Custom PGL™ pre-thermal conductance test (May 2018).
Important Limitations To Consider
First and foremost: don't confuse "single/monolayer graphene," with "graphene films/sheets/foils," or be deceived by claims regarding the durability of pyrolytic graphite and graphene sheets. Straps can be torn if mishandled during installation, flexed on the lateral axis, or if they are subjected to repeated flexing or movement on ANY axis (as this can cause localized creasing, damage, and eventual tearing of sheets). It is also important to understand that despite any claim to the contrary, all carbon materials; graphite, pyrolytic graphite, and graphene sheets/films/foils, will particulate, pose contamination risks, and generate FOD. As a result, all carbon-based straps must be encapsulated (typically with an aluminized mylar sleeve, or "blanket").
This does not mean that PGL™ and GTL™ products are not suitable for any application; only 
that they are ideal under certain circumstances, and environmental & operational conditions. Our experts will help you to determine which product best suits your operational environment and performance requirements, to ensure the success of your program.
Pictured (Top): All forms of graphite, pyrolytic graphite, and graphene foil/sheet present FOD & contamination risks (and must be encapsulated). (Bottom) First generation PGL/PGS thermal strap with tearing/mechanical failure due to improper handling during installation and removal from test fixture.
