A laser-based system to heat nuclear fuel pellets at high temperature

Area of Science:

• Nuclear Engineering
• Materials Science
• Thermal Analysis

Background:

• Annealing tests are crucial for understanding nuclear fuel behavior.
• Conventional heating methods face limitations in control and speed.
• Investigating thermophysical properties, microstructure, and gas release requires precise thermal treatment.

Purpose of the Study:

• To introduce a laser-heating technique as an alternative to conventional annealing for nuclear fuel research.
• To demonstrate controlled and isothermal heating of uranium dioxide (UO2) fuel pellets.
• To explore the potential for rapid heating rates and high temperatures in nuclear fuel analysis.

Main Methods:

• Development of an indirect laser-heating system using a two-compartment tungsten crucible.
• Utilizing a laser susceptor for efficient and homogeneous heating of the nuclear fuel sample.
• Employing two 500 W lasers to achieve target temperatures and heating rates.

Main Results:

• Successfully heated UO2 samples to 1500°C with a maximum heating rate of 30°C/s.
• Demonstrated the feasibility of isothermal and controlled heating using the proposed laser system.
• The system showed scalability for higher heating rates and temperatures with increased laser power.

Conclusions:

• The laser-heating method provides a viable and controllable alternative for nuclear fuel annealing studies.
• This technique can be adapted for various sample geometries and materials beyond UO2.
• The system's scalability suggests potential for advanced nuclear fuel performance research.