Solderless, flexible copper thermal straps fabricated from 100% oxygen-free high-conductivity (OFHC) copper cable or braid, used to provide high thermal conductance with mechanical compliance in spacecraft and cryogenic thermal management systems.
4C-PURE™ Cabled Copper Thermal Straps
Solderless, flexible copper thermal straps fabricated from 100% oxygen-free high-conductivity (OFHC) copper cable or braid, used to provide high thermal conductance with mechanical compliance in spacecraft and cryogenic thermal management systems.
Description
4C-PURE™ (Conductive Compliant Cabled Copper - PURE) Thermal Straps are Thermal Space Ltd.'s product line of pure copper thermal straps, fabricated in Boulder, CO from bundled and cabled high-purity OFHC copper wire strands captured into solid copper end fittings/terminals without solders, adhesives, fillers, binders, or non-metallic coatings — using 100 percent OFHC copper only. Copper braid can be substituted for cable to intentionally bias mechanical flexibility along one or more axes; both cable and braided strands are referred to as rope. The straps are designed to balance thermal conductance and mechanical flexibility: cable configurations with more, smaller-diameter wires provide greater mechanical flexibility than fewer, larger-diameter wires, and stranding/bundling/cabling parameters are tuned to control stiffness, bend radius, and range of motion, with only a small thermal performance dependence on wire count/diameter. The -CRYO series (4C-PURE-CRYO™) is intended for low-temperature service and includes material certifications for copper purity plus optional cryogenic testing to verify performance in cold applications; guidelines are provided to maintain efficient thermal interfacing through temperature cycling and to minimize parasitic thermal coupling between a cold strap and warmer surroundings. Straps use OFHC copper (C101/C10100, 99.99% purity) with a residual resistivity ratio (RRR) typically between 100 and 200, giving strong low-temperature thermal conductivity gains. The straps are commonly used as flexible thermal interfaces for cryocoolers (both regenerative types such as Pulse Tube and Stirling, and recuperative types such as Reverse-Brayton), on both the cold side and warm compressor interface, in sensitive instrument and optical systems. Standard and custom terminal (end-fitting) configurations are available, bolted, clamped, or bonded, with hole diameter and location controllable to 0.001-inch or better; standard geometries are generally lower cost. Thermal Space can hybridize the straps by directly integrating the copper cable technology with heat pipes and vapor chambers to combine flexibility with long-distance heat transport. Metallization options offered include Gold (Au), Silver (Ag), Nickel (Ni), and Tin (Sn) for thermal control and surface passivation; gold-coated straps offer the lowest surface emittance in the company's range. Services include rapid concept development (typically within a day of receiving requirements), predictive empirical modeling/analysis, client-approved fabrication drawings, repeatable fabrication and post-fabrication cleaning processes, and full verification testing including thermal testing, static and dynamic stiffness testing, mechanical vibration and shock testing, tensile testing, thermal cycling, and electrical grounding verification. Large-quantity fabrication (thousands of units) is supported, along with specification/statement-of-work development services, for both flight and non-flight systems. Where weight is the dominant design parameter, the company offers a separate carbon-based Thermal LyNX® strap product as an alternative.
Specifications
| Material | OFHC Copper (C101, C10100), 99.99% purity |
|---|---|
| Residual resistivity ratio (RRR) | Typically 100–200 |
| Terminal hole diameter/location tolerance | 0.001-inch or better |
| Metallization options | Gold (Au), Silver (Ag), Nickel (Ni), Tin (Sn) |
| Product lines | 4C-PURE™ (standard), 4C-PURE-CRYO™ (low-temperature service with material certification and optional cryogenic testing) |
| Fabrication attachment method | No solders, adhesives, fillers, binders, or non-metallic coatings |
| Production capacity | Fabrication in quantities of thousands of units |
