Neutron shielding for demanding conditions: VYAL™ resins

Result of a 20+ years R&D, patented VYAL™ resins are designed to withstand the most severe conditions. They are already in use for neutron protection in hundreds of transport/storage casks and for on-site shielding of naval & civil nuclear reactors.

• The Challenge

  Protection from radiation is a priority in every nuclear-related activity and shielding from neutrons is especially a concern. Moreover, traditional neutron shielding materials lack the thermal and mechanical properties required to meet the requirements of highly complex nuclear activities:

  • high temperatures,
  • shock resistance,
  • stability over time,
  • fire resistance,

  • etc.

  All that with easiness in manufacturing and work execution.

  
  

  
  

• The Solution

  A family of new neutron shielding materials was developed by Orano NPS for nuclear spent fuel in storage facilities and transport/storage casks, showing high shielding, mechanical and thermal capabilities.

  These innovative materials are composed of a thermosetting resin. The cross-linking of the polymer leads to a rigid three-dimensional lattice, solid and resisting to extreme conditions (up to 180°C for long-term use). 

  Their shielding ability for neutron radiation is related to a high hydrogen content (for slowing down neutrons) and a high boron content (for absorbing neutrons). Atomic concentrations are equal to 5.1022 at/cm³ for hydrogen and 9.1020 at/cm³ for boron.

  The manufacturing process is very simple, as it consists in mixing the fillers and pouring at ambient temperature. So it is reliable, easy to implement and allows a perfectly customised product:

  • it can either be poured in situ or machined from pre-manufactured blocks, allowing for complex form factors,
  • its fire-resistance allows for welding directly around it, unlike other neutron shielding materials.

  
  

  • The VYALTM resin has long-standing mechanical & thermal characteristics and performances, guarantying a safe long-term utilisation under constraint conditions:
    • Lifetime of at least 60 years
    • Up to 180°C for long-term use
    • Lightness (no overload on structures/packages)
    • Self-extinguishable product

  • Perfect customisation: easy-to-work capability (poured at ambient temperature and machinable) for easy implementation in complex designs with high level of constraints

  • Rely on Orano NPS’ expertise for your neutron-protection needs:
    • Design
    • Supply
    • Services

  
  

  
  

• Key Features

  • High neutron-shielding efficiency
  • Solid, high density, inert and long-lasting material: 60-year lifetime
  • High temperature performance: up to 180 °C for long-term use
  • Lightness
  • Shapeable and easy implementation
  • M1 Fire, M0 Fumes
  • Unique mechanical properties: 
    Young modulus: 4300 MPa (compression at 23 °C)
  • Thermal conductivity:
    • 0,807 W/m·K at 40 °C
    • 0,821 W/m·K at 160 °C
  • Specific heat
    • 1,07 J/g·°C at 40 °C
    • 1,59 J/g·°C at 160 °C
  • BIW (Banal Industrial Waste): easy management of surplus and wasted material

  
  

   

• Links

  

  Nuclear Package and Safety