A neutron absorbing insert for use in a fuel rack. In one aspect, the insert includes: a plate structure having a first wall and a second wall that is non-coplanar to the first wall; the first and second walls being formed by a single panel of a metal matrix composite having neutron absorbing particulate reinforcement that is bent into the non-coplanar arrangement along a crease; and a plurality of spaced-apart holes formed into the single panel along the crease prior to bending.

As a sintered body for a radiation shielding material, which can effectively shield mainly low-energy-level neutrons, that is, thermal neutrons and lower, slow neutrons, and has excellent physical properties such as bending strength and Vickers hardness, leading to high machining strength, a sintered body for a radiation shielding material comprising LiF ranging between 99 wt. % to 5 wt. %, and one or more fluorides selected from among MgF.sub.2, CaF.sub.2, AlF.sub.3, KF, NaF, and/or YF.sub.3 ranging between 1 wt. % to 95 wt. %, having physical properties of a relative density of 92% or more, a bending strength of 50 MPa or more, and a Vickers hardness of 100 or more, is provided.

As a sintered body for a radiation shielding material, which can effectively shield mainly low-energy-level neutrons, that is, thermal neutrons and lower, slow neutrons, and has excellent physical properties such as bending strength and Vickers hardness, leading to high machining strength, a sintered body for a radiation shielding material comprising LiF ranging between 99 wt. % to 5 wt. %, and one or more fluorides selected from among MgF.sub.2, CaF.sub.2, AlF.sub.3, KF, NaF, and/or YF.sub.3 ranging between 1 wt. % to 95 wt. %, having physical properties of a relative density of 92% or more, a bending strength of 50 MPa or more, and a Vickers hardness of 100 or more, is provided.

Methods and systems for stabilizing spent fuel assemblies from sodium-cooled nuclear reactors using Zamak are described herein. It has been determined that there is a synergism between Zamak and sodium that allows Zamak to form thermally-conductive interface with the sodium-wetted surfaces of the fuel assemblies. In the method, one or more spent fuel assemblies are removed from the sodium coolant pool and placed in a protective sheath. The remaining volume of the sheath is then filled with liquid Zamak. To a certain extent Zamak will dissolve and alloy with sodium remaining on the fuel assemblies. Excess sodium that remains undissolved is displaced from the sheath by the Zamak fill. The Zamak is then cooled until solid and the sheath sealed. The resulting Zamak-stabilized spent fuel assembly is calculated to have sufficient internal thermal conductivity to allow it to be stored and transported without the need for liquid cooling.

The present disclosure, in an embodiment, is a facility that includes a device configured to generate a beam having an energy range of 5 MeV to 500 MeV, a first radiation shielding wall surrounding the device, a second radiation shielding wall surrounding the first radiation shielding wall, radiation shielding fill material positioned between the first radiation shielding wall and the second radiation shielding wall forming a first barrier. In embodiments, the radiation shielding fill material includes at least fifty percent by weight of an element having an atomic number from 12 to 83, and a thickness of the first barrier is 0.5 meter to 6 meters.

The present disclosure, in an embodiment, is a facility that includes a device configured to generate a beam having an energy range of 5 MeV to 500 MeV, a first radiation shielding wall surrounding the device, a second radiation shielding wall surrounding the first radiation shielding wall, radiation shielding fill material positioned between the first radiation shielding wall and the second radiation shielding wall forming a first barrier. In embodiments, the radiation shielding fill material includes at least fifty percent by weight of an element having an atomic number from 12 to 83, and a thickness of the first barrier is 0.5 meter to 6 meters.

A radiation shielded vault structure includes a rigid outer structure comprising a plurality of rigid structural components that are interconnected at elongated joints to define an interior space. The structural components include a layer of lower atomic number (Z) material such as aluminum alloy and one or more layers of higher atomic number (Z) material titanium and/or tantalum. The vault structure may include radiation shield members extending along the elongated joints to provide radiation shielding at the elongated joints. The shield members comprise a higher atomic number (Z) material such as titanium or tantalum. The rigid structural components may comprise plate members that are interconnected along side edges thereof. End plates may be attached to the plate members to close off the interior space.

The present invention relates to rigid structures and composite materials thereof for providing radiation attenuation/shielding. Some embodiments pertain to a radiation shielding apparatus including: a plurality of positionable radiation-shielding stacks of tiles. The stacks are subsequently and adjacently arranged in a contiguous configuration. A tile positioning mechanism allows movement of tiles within a stack between a stacked (retracted) position and an extended position. In the extended position, the tiles of each of the plurality of radiation shielding stacks at least partially overlap tiles of subsequent and adjacent tile stack at corresponding opposing side-margins thereof.

The present disclosure relates to a radiation shield device comprising a sheet of material comprising a plurality of flaps, wherein the sheet comprises a barrier to ionizing radiation. The present disclosure also relates to a method for manufacturing said radiation shield device.

A neutron absorber apparatus for use in restoring reactivity control to a nuclear fuel rack. The apparatus comprises an elongated tubular insert assembly configured for insertion in a storage cell of the rack. First and second absorber plates, each formed of a boron-containing material, are coupled together by upper and lower stiffening bands at the insert extremities and form a longitudinally-extending cavity configured for receiving a fuel assembly. The absorber plates and stiffening bands may have a rectilinear cross sectional configuration in one embodiment. At least one elastically deformable locking protrusion mounted proximate to the lower end of the absorber plates lockingly engages an available lower edge disposed in the cell sidewall above its bottom end. This fixes the tubular insert axially in the cell, thereby preventing its withdrawal after installing the insert. In one embodiment, the edge may be the bottom of existing absorber sheathing in the cell.