Thermal Strap Testing

Thermal Space Ltd. Offers the most Comprehensive Range of Thermal Strap Verification Testing

Our test protocols have been established to provide complete space flight qualification for any of the thermal strap products that we design, analyze, and fabricate. Our customers can select either specific tests that demonstrate the requisite performance in their system or complete qualification testing to assure successful performance from deployment through in-situ operation. Our engineering team has extensive experience with each of the test methods below, and we can customize a test plan to validate performance in your system.

Thermal Strap Testing Services

Thermal Conductance Testing – Testing is conducted under vacuum conditions and involves measuring differential temperature across a thermal strap while a heat load is applied to one end. The result is heat transport (W), per degree of temperature drop (K) to determine the thermal conductance (W/K) across a strap. Further, the test results typically include the effect of the thermal interfaces with the straps whether bolted, clamped, or bonded in the actual application. Testing can be conducted across a temperature range from 400 K to 80 K.  A complete description of this testing can be found here.

Mechanical Stiffness Testing – This test procedure is used to measure the static mechanical stiffness (also commonly referred to as the spring rate) of a thermal strap over a prescribed range of motion. The testing is typically conducted in one or more of the three linear axes of a strap to determine the force that is imparted at the strap terminal interfaces. A detailed description of this testing can be found here.

Thermal Cycling – Typically a survivability test, we can perform thermal cycles into the thousands of excursions between 200°C and -200°C, and in special instances down to -270°C. Thermal cycling below 10°C is usually performed under vacuum conditions.

Vibration and Shock Testing – We partner with a MIL approved and ISO accredited test facility to test our products to all the way up to high-level vibration and shock environments required in many military and aerospace systems. Testing can include sine sweep, sine dwell, random vibration, sine-on-random vibration, typical shock, and shock response spectrum. A frequency range from 3 to 3,000 Hz can be accommodated with maximum forces: shock- 65,000 lbf, sine – 25,000 lbf, and random – 22,000 lbf.  Acceleration limits are around 200 g. We can also accommodate this testing at cryogenic temperature down to 80 K.

Dynamic Stiffness Testing – Dynamic stiffness behavior can be very different from static stiffness behavior in a thermal strap. For applications that require frequency dependent force damping, we can provide thermal strap characterization of transported forces all the way in to the 1000s of Hz frequency range. While this is somewhat specialized testing, our engineering team has the experience to develop and implement relatively simple test plans and procedures to get accurate data, including temperature dependent stiffness down to around 100 K.

Tensile Strength Testing – While it is rare that a thermal strap is intended to be a load-bearing element, there are potential scenarios where a strength limit could be levied upon a fully extended thermal strap. Tensile strength testing of a thermal strap is straightforward and can be conducted to prescribed survivability levels or to determine failure limits in specific designs.

Fatigue Testing – When a thermal strap is subjected to repeated mechanical cycles (range of motion), there can be concern for material fatigue and possible failure in areas where stresses are concentrated. To demonstrate longevity in these cases, we provide mechanical range of motion testing. This testing can be conducted at an accelerated rate to provide up to tens of millions of cycles to verify that either fatigue limits or cold working (change in stiffness) are not an issue.

Contamination Testing – Typically less of an issue for metal and graphene-based thermal straps, contamination was a huge issue for now obsolete graphite fiber thermal straps because the individual fibers unavoidably fracture and fray leaving a debris field that is highly threatening to many sensor and optical systems. Still, in some extremely-sensitive systems any threat of contamination, whether volatile or particulate in form, may necessitate the characterization of both the source and any potential contaminate. Specialized testing for volatile residues and particle measuring can be conducted to evaluate any potential threat based upon strap utilization and environment.  The outcome of such testing is either verification that contamination is not an issue or to create a mitigation plan that assures contaminates will not compromise any system performance parameter.