Black tungsten wire, with its unique physical and chemical properties, is an indispensable material in high-temperature furnace applications, excelling in environments requiring extreme temperatures, high purity, or vacuum conditions.
1. Heating Element (Core Application)
- Role in High-Temperature Furnaces: Black tungsten wire serves as a key heating element in resistance heating furnaces (e.g., muffle furnaces, tube furnaces, vacuum furnaces). It generates Joule heat (Q = I²Rt) when current passes through, converting electrical energy into thermal energy for precise furnace temperature control.
- Advantages:
- High-Temperature Resistance: Can operate continuously above 1600°C and withstand short-term temperatures exceeding 2000°C, far surpassing other metallic materials (e.g., nickel-chromium alloys, limited to ~1100°C).
- Uniform Heating: Its high resistivity (approximately 5.6×10⁻⁸ Ω·m) ensures even heat distribution, avoiding localized overheating.
- Long Lifespan: In inert atmospheres (e.g., argon) or vacuum environments, black tungsten wire’s oxidation rate is extremely low, significantly extending its service life.
2. Temperature Sensors and Thermocouple Protection Sheaths
- Temperature Measurement: Black tungsten wire can be used as a lead or protective sheath for thermocouples to measure extreme furnace temperatures (e.g., above 1800°C). Its low thermal expansion coefficient (4.5×10⁻⁶/°C) and high-temperature stability ensure measurement accuracy.
- Protective Role: In oxidative or corrosive environments, coated black tungsten wire protects thermocouples from degradation, extending sensor lifespan.
3. Support Structures and Fixtures
- Furnace Supports: The high strength and heat resistance of black tungsten wire make it ideal for supporting samples or crucibles, particularly in vacuum or controlled-atmosphere furnaces, where it prevents metal contamination of samples.
- Electrode Material: In arc furnaces or plasma furnaces, black tungsten wire serves as an electrode, withstanding high-temperature arc erosion while maintaining structural stability.
4. Specialized Components for Vacuum and Inert Atmosphere Furnaces
- Vacuum Sealing: Black tungsten wire is used in seals or connectors for vacuum furnaces due to its low vapor pressure (approximately 10⁻⁴ Pa at 2000°C), preventing contamination of the vacuum system.
- Gas Diffusion Barrier: In atmosphere furnaces, coated black tungsten wire reduces gas permeation, maintaining the purity of the furnace atmosphere.
5. Support for Specialized Processes
- Chemical Vapor Deposition (CVD): Black tungsten wire acts as a heating element in CVD processes, providing a high-temperature environment to promote the growth of thin-film materials (e.g., silicon carbide, gallium nitride).
- Heat Treatment and Annealing: In metal heat treatment, black tungsten wire furnaces enable precise temperature profile control, optimizing material properties (e.g., hardness, toughness).
6. Optical and Semiconductor Applications
- Infrared Heating: The infrared wavelength emitted by black tungsten wire (approximately 1–10 μm) matches the absorption peaks of many materials, enabling efficient heat transfer for applications like semiconductor wafer annealing or optical coating.
- Halogen Lamp Filaments: While not a traditional high-temperature furnace, black tungsten wire in halogen lamps serves as a light-emitting filament, withstanding instantaneous temperatures above 2500°C, demonstrating its extreme heat resistance.
More details of tungsten wire, please visit website: http://www.tungsten-wire.com.cn/
Please contact CHINATUNGSTEN for inquiry and order of tungsten wire:
Email: sales@chinatungsten.com
Tel.: +86 592 5129595
