Syllabus Coverage: NFC2.1
The cladding is a sleeve around the fuel rod. It serves several critical purposes:
- Prevents corrosion of the fuel by the coolant
- Retains fission products — keeping radioactive material contained
- Accommodates fuel volume changes during irradiation
- Provides a surface for heat transfer from the fuel to the coolant
To be effective, a cladding material must have:
- Low thermal neutron absorption cross-section (so it does not waste neutrons)
- High corrosion resistance
- Compatibility with the fuel
- High resistance to radiation damage
- Good mechanical strength
- High thermal conductivity