Thin Metal Foil Thermal Straps (TMF Series™)
Thermal Space Ltd.
The TMF Series™ Thin Metal Foil Thermal Straps, including Copper Foil Straps (CuFS™) and Aluminum Foil Straps (AlFS™), offer superior thermal and mechanical performance for various applications, providing volume-efficient and contamination-resistant thermal links.
Technical specifications
- Copper type/purity
- Electrical Tough Pitch (ETP), C110/99.9%
- Rrr range
- 50-100
- Copper type/purity (2)
- Oxygen Free High Conductivity (OFHC), C101/99.99%
- Rrr range (2)
- 100-500
- Copper type/purity (3)
- 4N/99.99%
- Rrr range (3)
- 500-2,000
- Copper type/purity (4)
- 5N/99.999%
- Rrr range (4)
- 1,000-10,000
- Aluminumtype/purity
- 1100/99%
- Rrr range (5)
- 10-50
- Aluminumtype/purity (2)
- 1050/99.5%
- Rrr range (6)
- 20-80
- Aluminumtype/purity (3)
- 3N/99.9%
- Rrr range (7)
- 35-105
- Aluminumtype/purity (4)
- 4N/99.99%
- Rrr range (8)
- 100-5,000
- Aluminumtype/purity (5)
- 5N/99.999%
- Rrr range (9)
- 150-10,000
About
The TMF Series™ Thermal Straps are designed to provide superior thermal and mechanical performance in a wide range of applications. These thermal links, also known as thermal shunts or heat straps, offer highly volume-efficient and contamination-resistant packaging. The series includes two main types: Copper Foil Straps (CuFS™) and Aluminum Foil Straps (AlFS™).
CuFS™ are available in various copper purities, including ETP (C110), OFHC (C101, 4N purity), 5N purity, and in rare cases, 6N ultra-purity. ETP copper foil thermal straps are recommended for temperatures above 40 K, while OFHC copper foil thermal straps are ideal for use below 40 K. Higher purity options like 5N and 6N copper provide significantly superior performance at temperatures below 25 K, though with increased material cost and limited availability for 6N. The thermal conductivity of copper is highly dependent on its Residual Resistivity Ratio (RRR), which varies with purity. CuFS™ can be configured up to several feet in length and nearly any practical width and cross-section, with individual foil thickness adjustable for optimal thermal conductance, mechanical flexibility, and cost. Gold coating is available for copper straps using a specialized process to enhance thermal control and mitigate oxidation.
AlFS™ are constructed from aluminum foil and end fittings, with purities ranging from 99% (Al1100) to 99.999% (5N). Al1100 is suitable for most applications, while higher purity options are attractive for low-temperature use. Aluminum straps are often preferred over copper in mass-limited applications due to aluminum’s lower density, despite its lower thermal conductivity. Similar to copper, aluminum’s thermal conductivity improves significantly at lower temperatures with higher RRR values, becoming particularly attractive below 70 K on a thermal conductivity to mass basis. Standard AlFS™ are made from Al 1100 and can be fabricated in dimensions from less than an inch up to several feet in both width and length. Foil thickness can be selected for optimal thermal conductance, flexibility, and cost. The engineering team also provides expertise in metallization and interfacing techniques for aluminum straps to ensure efficient performance, especially in extreme cryogenic temperature ranges.
Documentation
No public datasheet yet — request the datasheet / ICD from the supplier.