INVESTIGATION of SWELLING BEHAVIORS of U-10ZR METALLIC FUEL in the LOW TEMPERATURE REGIME VIA A COMBINED THERMO-MECHANICAL and RATE THEORY ANALYSIS

Uranium zirconium (U-Zr) metallic nuclear fuel has long been considered as a promising candidate for fast reactor fuel in the past few decades duo to its excellent performance. One of the key performance problems of U-10Zr metallic fuel is its strong swelling which would lead to significant fuel cladding mechanical interaction (FCMI) at high burn-ups. Therefore, the mechanism of fuel swelling has long been a concern of great interest in a wide range of this fields. Recently published research conducted by the Institute of Nuclear Physics and Chemistry in China got the experimental results of U-10Zr fuel swelling in a low temperature regime (400-600K) which showed perceivable swelling of the in-pile irradiated fuel. The previous exploration on the swelling mechanism of uranium zirconium metal fuel at low temperature can't be carried out due to the lack of data and this research filled the gap for the swelling data of uranium zirconium metallic fuel at low temperature. In our work, combined with the input parameters given by finite element analysis, we utilized a rate theory code based on the cavitational void swelling model to catch the fuel swelling behaviors of the U-10Zr fuel in the low temperature regime building upon these data. And a new set of key parameters for the rate theory model were also determined.