In fiber optic applications, the most hidden and destructive threat does not come from visible shock or corrosion, but from moisture. In high-humidity, high-pressure, or high-temperature steam environments, water diffuses into microscopic defects on the surface of the silica glass, causing the fiber's strength to gradually decline under constant stress, ultimately leading to catastrophic failure—this is known as Static Fatigue, or Hydrolysis Fatigue.
For critical applications that demand long-term stability in extreme environments, such as downhole oil and gas, submarine communications, or hot and humid areas, traditional polymer coatings (like polyimide) cannot provide sufficient protection.
[Beijing Dacheng Yongsheng Technology Co., Ltd. (DCYS)] offers the OFSCN® Gold-Coated Fiber, which provides a permanent solution through its unique metallic coating technology.
I. The Mechanism of the "Invisible Killer": Hydrolysis Fatigue
Hydrolysis fatigue is one of the primary causes of fiber failure. The process unfolds as follows:
- Defect Invasion: Microscopic cracks and flaws appear on the surface of the silica glass, either during manufacturing or when the fiber is stressed.
- Moisture Reaction: Water molecules (H2O) from the environment penetrate these defects.
- Crack Propagation: Under continuous tensile stress, the water molecules chemically react with the silica (SiO2) bonds (hydrolysis), causing the cracks to slowly and steadily grow.
- Final Fracture: After extended service time, the crack reaches a critical size, and the fiber suddenly breaks under stress far below its original strength.
II. Gold Coating: Constructing a True "Hermetic Barrier"
To completely eliminate hydrolysis fatigue, moisture must be prevented from contacting the silica glass surface. The gold coating is the “hermetic armor” designed to achieve precisely this goal.
1. Physical Isolation: Zero Moisture Permeation Rate
Gold-coated fiber uses high-purity gold, applied directly onto the silica cladding via electroplating or similar processes.
- Metal Density: The gold layer forms a non-permeable metallic barrier. Compared to any polymer material (even carbon coating), the density of the metallic coating is orders of magnitude higher, and its permeability to gas and moisture is virtually zero.
- Eliminating Fatigue: Once water molecules are blocked from reaching the glass surface, the chemical reaction chain of hydrolysis is permanently severed, and the fiber’s static fatigue phenomenon is eliminated. The long-term life and reliability of gold-coated fiber are thus fundamentally guaranteed.
2. Superior Hydrogen Darkening Protection
In addition to moisture, the permeation of hydrogen molecules (H2) can cause hydrogen darkening in the fiber at high temperatures. The hermeticity of the gold layer is equally effective against smaller hydrogen molecules, allowing it to completely block hydrogen diffusion and ensure the fiber's attenuation stability in hydrogen-rich environments (such as downhole).
III. The Value and Application Scenarios of Gold-Coated Fiber
Choosing OFSCN® Gold-Coated Fiber means choosing the highest level of environmental protection.
|
Value Advantage |
Application Scenarios |
|
Permanently eliminates static fatigue |
Submarine cables, deepwater sensors, long-term monitoring in high-humidity tropical regions. |
|
Ultra-high temperature resistance (up to 700°C) |
Geothermal wells, high-temperature steam environments, inside nuclear reactors. |
|
Ultra-long service life |
Oil and gas downhole (10+ years), critical military systems, and non-maintainable key infrastructure. |
In "mission-critical" applications where repair costs are extremely high, downtime losses are significant, or the consequences of failure are intolerable, gold-coated fiber provides unparalleled long-term reliability.
[Beijing Dacheng Yongsheng Technology Co., Ltd. (DCYS)] specializes in providing a full range of specialty fiber solutions from -269°C to +700°C.
Feel free to contact us to inquire about splicing and termination solutions for gold-coated fiber or to consult on its application in your specific high-humidity and high-pressure environment.
[Beijing Dacheng Yongsheng Technology Co., Ltd. (DCYS)]
Official Website: https://www.ofscn.org
Product Link: https://www.ofscn.org/optical-fibers/gold-coated.html