Metal-Hydride Moderators
Hydrogen Bearing Moderators
ZrHx, YHx, H2O
Hydride moderators are simply hydrogen containing materials that can be used to moderate neutrons in nuclear reactors. They are extremely effective neutron moderators that allow reactor cores to be small – without using high enrichments. Think trash can sized
Zirconium hydride (ZrHx), yttrium hydride (YHx), and H2O are the three most promising moderator materials in terms of the moderating ratio, which is the ratio of the macroscopic slowing-down power (the product of the average logarithmic energy loss per collision and the macroscopic neutron scattering cross section) to the macroscopic cross section for neutron absorption.
SiC Can Cap
YHx Pellets
SiC Can Base
Metal-Hydride Can
Simple + Robust Design
We use additive manufacturing to create a silicon carbide container that holds the metal-hydride pellets. Our techniques and design methods allow for a variety of moderator form factors including different diameters and lengths and novel geometric forms. The container is gas-tight to very high temperatures and pressures.
Why Metal-Hydrides?
USNC has developed and patented the techniques and configurations to deliver hydrides for nuclear reactors so that they can achieve high temperatures and robust performance. We are proud to be able to supply the nuclear industry with next generation moderators that allow for very small cores. The R&D efforts were supported by NASA SBIRs and internal funding.
Higher Temperatures
Although H20 has been used in nuclear reactors since the beginning of the industry, both as coolant and moderator, its application as a high temperature (>400 °C) moderator material is restricted by the requirement for extremely high pressure. Properly manufactured metal-hydride moderator can allow for reactor temperatures in excess of 800 °C.
Reduced Core Size
Metal-hydrides offer an alternative to graphite moderator in high temperature gas cooled reactors (HTGR). The biggest advantage is a reduction in core size, allowing for a smaller pressure vessels and greater fuel efficiency. Reducing core volume and mass is crucial for space power applications.
Yttrium Hydride
We offer manufacturing of highly dense and robust yttrium hydride parts in a wide range of geometries for various applications. Our bulk metal hydriding technology delivers highly accurate H/Y ratios to meet customer specifications with x in YHx varying between 1-1.85. We can manufacture parts to meet high tolerance requirements. Our manufacturing is performed with high quality, and upon request, may be performed in compliance with NQA-1.
Zirconium Hydride
We offer manufacturing of highly dense and robust zirconium hydride parts in a wide range of geometries for various applications. Our bulk metal hydriding technology delivers highly accurate H/Zr ratios to meet customer specifications with x in ZrHx varying between 1-1.6. We can manufacture parts to meet high tolerance requirements. Our manufacturing is performed with high quality, and upon request, may be performed in compliance with NQA-1.