DESC0023875

C56-40e-273310 Nuclear microreactors producing < 20 MW of power are being researched for portable and on-site energy production in situations such as disaster relief, mobile encampments, or remote locations where access to the regional power grid is limited or difficult. In order to facilitate this mass production of nuclear reactors, radiation shielding must be produced which is reliable, replaceable, and lightweight for both transportation and maintenance during use. Modular shielding is ideal for this situation, allowing for simple mass- production and assembly. The need for simplified shielding can be solved by creating a novel lightweight composite material to be used as a radiation absorber for all relevant radiation types. Aluminum-based metal matrix composites with tungsten gamma absorbing and boron-carbide neutron absorbing (B4C) reinforcements will be developed for mass production. Phase I will involve developing and testing small-scale metal matrix composites with radiation blocking capability. Initial compositions and designs will be optimized, then tested for mechanical and thermal stability. Composite parts will be subjected to radiation testing, and then modeled to predict material thickness needed for full-scale specimens to block the necessary level of radiation. Developing light weight composite microreactor shielding materials will enable the proliferation of reliable, low-cost nuclear energy production. The modular composites will be cheaper to produce than custom designs, and easier to replace if damaged or during regular maintenance. Further, the production process will lend itself to rapid development of additional composites using novel radiation absorbers. As safer, more lightweight, or lower cost absorbers are discovered, the production process can be easily modified to introduce and test updated compositions for radiation shielding in the future.