CFC Springs
Manufactured from carbon fiber reinforced carbon matrix composite (C/C composite) — deliver controlled, repeatable spring force at process temperatures up to 2200°C in vacuum, where every metal alternative fails. With a density of just 1.7 g/cm³, near-zero thermal expansion, and full chemical inertness, they are the engineered replacement for metallic springs and deadweights in vacuum brazing fixtures, heat treatment assemblies, and high-purity furnace systems. Max Graphite supplies CFC springs in standard and fully custom configurations, precision-machined to your load, travel, and dimensional specifications.
Metal springs — whether Inconel, molybdenum, or stainless steel — impose hard constraints on high-temperature process design. CFC springs remove those constraints without compromise on mechanical function.
Technical Specifications
All values are typical and subject to variation. For technical data sheets or custom recommendations, please contact Max Graphite.
Configurations and Customization
Max Graphite CFC springs are available in standard coil and disc (sprung washer) configurations and are fully customizable by outer diameter, inner diameter, free length, and spring constant. All springs are precision-machined from C/C composite block stock.
Available Configurations:
- Coil Springs — Standard helical coil form for compression applications in brazing fixtures and heat treatment assemblies; available in multiple OD/ID/free length combinations
- Sprung Washers / Disc Springs — Flat or dished disc form for applications with constrained axial space; distributes preload or compensates for thermal expansion across a broad contact surface under bolt heads, nuts, or clamping elements
- Custom Spring Geometry — Any combination of outer diameter, inner diameter, free length, wire cross-section, and coil pitch machined to drawing; minimum run quantities apply
- SiC Coating — Silicon carbide surface coating available for applications requiring enhanced oxidation resistance above 400°C or improved surface hardness
- PyC / PyG Coating — Pyrolytic carbon or pyrolytic graphite coating available for ultra-high-purity applications requiring minimal particulate generation
- Precision CNC Machining — All springs machined from block or billet CFC stock; tight tolerances on all critical dimensions to drawing
- Assembly-Ready Supply — Springs can be supplied as discrete components or integrated into custom graphite/CFC fixture assemblies per customer design
Applications
- Vacuum Brazing Fixtures — Replace deadweights with defined, repeatable spring force at brazing temperatures (typically 800–1200°C); enables more consistent joint quality and fixture miniaturization through reduced fixture mass
- Heat Treatment Clamping Assemblies — Maintain controlled clamping force on components during case hardening, annealing, and solution heat treatment cycles in vacuum and inert-atmosphere furnaces; eliminates metal spring creep and contamination
- Sintering Fixtures — Apply and maintain pressure on powder metal or ceramic compacts during solid-state sintering at temperatures above 1000°C, where metallic spring elements lose mechanical function
- Semiconductor Wafer Carriers and Susceptor Assemblies — Provide compliant clamping with zero metallic contamination risk in high-purity CVD, epitaxy, and diffusion furnace environments
- Solar / PV Crystal Growth Systems — Structural spring elements in crucible and heater assemblies operating in argon or vacuum at temperatures exceeding 1400°C
- Aerospace Structural Brazing — High-reliability spring clamping for aerospace-grade brazed joints in nickel superalloy and titanium structures where contamination and dimensional consistency are specification-controlled
- Diffusion Bonding Tooling — Apply sustained, calibrated pressure on bonding interfaces at elevated temperature and pressure in vacuum diffusion bonding presses
- Mechanical Sealing in High-Temperature Environments — Compliant spring elements in non-oxidizing shaft seal and valve assemblies operating continuously above 600°C
