Effect of particle size and percentages of Boron carbide on the thermal neutron radiation shielding properties of HDPE/B₄C composite: Experimental and simulation studies

In this paper the effects of particle size and weight percentage of the reinforcement phase on the absorption ability of thermal neutron by HDPE/B₄C composites were investigated by means of Monte-Carlo simulation method using MCNP code and experimental studies. The composite samples were prepared using the HDPE filled with different weight percentages of Boron carbide powder in the form of micro and nano particles. Micro and nano composite were prepared under the similar mixing and moulding processes. The samples were subjected to thermal neutron radiation. Neutron shielding efficiency in terms of the neutron transmission fractions of the composite samples were investigated and compared with simulation results. According to the simulation results, the particle size of the radiation shielding material has an important role on the shielding efficiency. By decreasing the particle size of shielding material in each weight percentages of the reinforcement phase, better radiation shielding properties were obtained. It seems that, decreasing the particle size and homogeneous distribution of nano forms of B₄C particles, cause to increase the collision probability between the incident thermal neutron and the shielding material which consequently improve the radiation shielding properties. So, this result, propose the feasibility of nano composite as shielding material to have a high performance shielding characteristic, low weight and low thick shielding along with economical benefit. - Highlights: • The radiation shielding properties of the nano composite and micro composite were compared in experimental and simulation. • The particle size of the radiation shielding material is an important role on the shielding efficiency. • In order to provide more effective shielding, the nano particles should be uniformly distributed to the polymer matrix. • By use of B₄C nano particles, light weight radiation shielding composite can be constructed.