Outstanding thermal neutrons shields based on epoxy, UHMWPE fibers and boron carbide particles

Highlights: • Lightweight hybrid composites were designed with excellent neutron shielding ability. • UHMWPE fibers could efficiently replace PE polymers in structural shields. • UHMWPE/epoxy composite with 20 wt% B₄C particles showed the best results. • Excellent combination between neutrons shielding and mechanical performances. Aiming the development of advanced and lightweight thermal neutrons shields, a new hybrid composite was developed from UHMWPE fibers, epoxy and boron carbide (B₄C) particles. The UHMWPE fibres were chosen because of their high hydrogen contents and exceptional mechanical properties. The neutrons shielding tests were performed using an optimized experimental setup at NUR research reactor, Algiers. Overall, the developed materials displayed remarkable neutrons screening performances. Meanwhile, the best performance was recorded at B₄C amount of 20 wt% with a macroscopic cross-section (Σ) of with a 0.313 cm⁻¹ equivalent to a mean free path (λ) of 2.2 cm.