Research on a bimetallic-sensitized FBG temperature sensor.

Area of Science:

• Materials Science
• Sensor Technology
• Physics

Background:

• Accurate temperature measurement is crucial for structural health monitoring and earthquake prediction.
• Standard fiber Bragg grating (FBG) sensors often exhibit limited sensitivity for these applications.

Purpose of the Study:

• To develop a highly sensitive FBG temperature sensor using a bimetallic sensitization structure.
• To analyze and optimize the structural parameters for improved sensor performance.

Main Methods:

• Theoretical analysis of substrate and strain transfer beam dimensions and materials.
• Selection of 7075 aluminum and 4J36 invar as bimetallic materials.
• Design, fabrication, and performance testing of the bimetallic-sensitized FBG sensor.

Main Results:

• The developed FBG temperature sensor achieved a sensitivity of 50.2 pm/°C.
• This represents approximately a fivefold increase in sensitivity compared to bare FBG sensors.
• The sensor demonstrated excellent linearity with a value greater than 0.99.

Conclusions:

• The bimetallic sensitization approach effectively enhances FBG temperature sensor sensitivity.
• The optimized sensor design provides a reliable and sensitive tool for temperature monitoring.
• This research offers valuable insights for developing advanced FBG sensors with superior performance.