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arXiv · 1604.08496

Scoping of material response under DEMO neutron irradiation: comparison with fission and influence of nuclear library selection

Abstract

Predictions of material activation inventories will be a key input to virtually all aspects of the operation, safety and environmental assessment of future fusion nuclear plants. Additionally, the neutron-induced transmutation (change) of material composition (inventory) with time, and the creation and evolution of configurational damage from atomic displacements, require precise quantification because they can lead to significant changes in material properties, and thus influence reactor-component lifetime. A comprehensive scoping study has been performed to quantify the activation, transmutation (depletion and build-up) and immediate damage response under neutron irradiation for all naturally occurring elements from hydrogen to bismuth. The resulting database provides a global picture of the response of a material, covering the majority of nuclear technological space, but focussing specifically on typical conditions expected for a demonstration fusion power plant (DEMO). Results from fusion are compared against typical fission conditions for selected fusion relevant materials, demonstrating that the latter cannot be relied upon to give accurate scalable experimental predictions of material response in a future fusion reactor. Results from different nuclear data libraries are also compared, highlighting the variations and deficiencies.

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M. R. Gilbert, J. -Ch. Sublet. 2016-04-27. Scoping of material response under DEMO neutron irradiation: comparison with fission and influence of nuclear library selection. https://arxiv.org/abs/1604.08496

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