APPLICATION OF AL-B_4C METAL MATRIX COMPOSITES IN THE NUCLEAR INDUSTRY FOR NEUTRON ABSORBER MATERIALS

摘要

For dry storage and transport of spent nuclear fuel in the nuclear industry, the most commonly used neutron absorbers are boron-containing metallic materials, in which the boron element possesses a high cross-section for absorbing thermal neutrons. Al-B_4C Metal Matrix Composites (MMCs), recently developed by Alcan, are particularly suitable for manufacturing high quality neutron absorber components due to the flexibility of adding various boron concentrations, the lightweight, the superior thermal conductivity and the mechanical properties. In this paper, the process route for manufacturing Al-B_4C composites and the technical challenge are presented. Results of neutron absorption based on neutron transmission testing for typical Al-B_4C composites produced in the industrial scale are described. A series of Al-B_4C MMCs with different Al-matrix alloys and B_4C loads are introduced for both structural and non-structural applications. The composites can be cast, extruded or rolled to almost any desired size and shape. The typical microstructure, mechanical properties and thermal conductivity of some Al-B_4C products are reported.