The Advancement of Neutron Shielding Materials for the Storage of Spent Nuclear Fuel

Abstract

With the development of nuclear industry, spent nuclear fuel (SNF) generated from nuclear power plants arouses people’s attention as a result of its high radioactivity, and how to guarantee the reliable operation of nuclear facilities and the staff’s safety occupies a crucial position. To avoid the lethal irradiation, a lot of functional neutron shielding composites have been developed to transform fast neutrons into thermal neutrons which can be absorbed with high macroscopic cross-sectional elements. Irradiation characteristics of nuclear industry have promoted the advancement of neutron shielding materials. Here, we review the latest neutron shielding materials for the storage of spent nuclear fuel containing additives such as boron carbide (B4C), boron nitride (BN), boric acid (H3BO3), and colemanite. Different types of neutron shielding materials, including metal matrix alloys, polymer composites, high density concrete, heavy metals, paraffin, and other neutron shielding composites with high macroscopic cross-sectional elements, arediscussed. The elemental composition, density, and thermal and mechanical properties of neutron shielding materials are also summarized and compared.

An Optimal Design Method for Improving the Efficiency of Ultrasonic Wireless Power Transmission during Communication

“…Modern equipment, such as engines, nuclear material containers, missiles, submarines, space stations [ 1 , 2 , 3 , 4 ], are protected by sealed metal structures to adapt to unique environments, such as high temperature and high pressure or special use requirements. In some cases, the equipment needs to penetrate the sealed metal casing to transmit necessary data and energy during long-term operation, for example, the health monitoring of aero engines and the wireless power and data transmission between some sealed compartments of submarines [ 5 , 6 , 7 , 8 ].…”

[B10H10]2– Nanoclusters Covalently Immobilized to Hybrid SiO2 Aerogels for Slow Neutron Shielding Applications

“…Generally, polymer neutron absorbing materials are vulnerable to irradiation damage. 5 With the increase in the irradiation dosage, polymer-based materials undergo chemical and structural transformations resulting in reducing the molecular weight and emission of various gases (including CO, CH 4 ), which lead to the formation of voids in the polymer matrix reducing its mechanical strength and shielding efficiency. 5 The weight of the neutron capturing materials is another parameter of primary importance for the protection of oncology patients during boron neutron capture therapy.…”

“…5 With the increase in the irradiation dosage, polymer-based materials undergo chemical and structural transformations resulting in reducing the molecular weight and emission of various gases (including CO, CH 4 ), which lead to the formation of voids in the polymer matrix reducing its mechanical strength and shielding efficiency. 5 The weight of the neutron capturing materials is another parameter of primary importance for the protection of oncology patients during boron neutron capture therapy. Despite the relatively light weight of polymer materials, they possess a typical density of around 1 g/cm 3 , 6 which gives more than 2 kg per single borylated polymer slab in a typical therapeutical procedure.…”

Study on a High-Boron-Content Stainless Steel Composite for Nuclear Radiation

“…Generally, as the boron content increases, the thermal neutron absorption capacity will increase but ductility, impact toughness, and corrosive resistance will decrease [8]. Because of the low solubility limits of the B element in borated stainless steel, excessive addition of boron will cause the formation of a fragile phase (Fe,Cr) 2 B making it difficult to prepare borated stainless steel [9,10]. The ASTM standard A887 covers eight types of BSS according to their content of B, and the weight percentage of boron is only 0.2-0.25 wt% [11].…”

“…According to the above principles, it is possible to reduce the weight of BSS while keeping its neutron shielding performance unchanged by increasing the content of B and C and decreasing that of Fe. Considering the low solubility limits of boron in borated stainless steel [9] and the high boron content in B 4 C, if more B 4 C is added to the matrix material, the content of B can be increased. Because the density of B 4 C is 2.52 g cm −3 , the higher its content is, the smaller the density of the composite is.…”