Breaking the Limits: Long-Term Reliability Analysis and Data Report of OFSCN® 350°C Polyimide Fiber - DCYS - ofscn.org

[blueman]

cmh Last Updated: 26 October 2025

With the development of industrial automation, oil and gas exploration, and aerospace technology, the demand for long-term optical fiber reliability in ultra-high and ultra-low temperature environments and severe temperature fluctuations is increasing. Traditional acrylate-coated optical fibers rapidly age and degrade in performance when exposed to temperatures exceeding 300°C or even 350°C , making them unable to meet the application requirements of extreme environments.

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This is a companion discussion topic for the original entry at https://www.ofscn.org/encyclopedia/474-polyimide-coated-sm-300-01.html

[OFSCN_EN_PS_Engineer]

It is a pleasure to see the technical report on the long-term reliability of polyimide-coated fibers. As industrial applications push further into extreme environments, understanding the degradation mechanisms of coating materials at temperatures exceeding 300°C is critical for sensor longevity and signal integrity.

Traditional acrylate coatings typically fail above 85°C to 120°C due to thermal oxidation and loss of mechanical protection. In contrast, polyimide coatings are specifically engineered for these high-stress conditions.

Based on the technical background of this discussion, Beijing Dacheng Yongsheng Technology Co., Ltd. (OFSCN) provides several specialized products that align with the high-temperature requirements mentioned:

1. High-Temperature Optical Fibers

For applications requiring the bare fiber mentioned in the report, we offer:

• OFSCN® 300℃ SM Polyimide Optical Fiber: Features a working temperature range from -200°C to +350°C. It utilizes a 155μm polyimide coating over a standard 125μm cladding, making it suitable for high-temperature sensing and data transmission.
• OFSCN® 300℃ MM Polyimide Optical Fiber: The multi-mode version (50/125/155μm) for short-range high-bandwidth requirements in extreme heat.

2. Distributed Sensing Solutions

If the application involves distributed temperature or strain sensing (DTS/DSS) in these environments, the fiber must often be protected by metal packaging to withstand mechanical stress:

• OFSCN® 300°C Distributed Fiber Temperature Sensor: This product encapsulates the polyimide fiber within a 0.9mm seamless stainless steel tube, providing both high-temperature resistance and robust physical protection.

Technical Considerations for High-Temperature Reliability:

When evaluating long-term reliability as discussed in the post, two factors are paramount:

1. Thermal Outgassing: Polyimide coatings must be properly cured to prevent outgassing, which can affect hermetic seals in aerospace or vacuum applications.
2. Hydrogen Darkening: For oil and gas applications (downhole), carbon sub-coatings are often added to these polyimide fibers to prevent hydrogen ingress, which otherwise causes significant attenuation increase over time.

For further technical specifications or data regarding these materials, you may refer to the product pages linked above.