Characterization of Be Deposits on Mo, W and Cu Substrates, to Implement in a Neutron Production Target for Accelerator-based Boron Neutron Capture Therapy

摘要

The generation of neutrons through nuclear reactions like Be(d,n), necessary to implement Accelerator-Based Boron Neutron Capture Therapy (AB-BNCT), requires stable Be deposits on an adequate substrate. In this paper, first results of beryllium deposits on Mo, W and Cu substrates are shown. In order to achieve the adhesion of the deposits on the different substrates, powder blasting tests under different conditions were made. On the other hand, silver deposits were made on some of the samples, previously blasted, to favor the chemical affinity between beryllium and the substrate thus improving adhesion, Knowles and Hazlett (1970). Beryllium deposits, on these previously treated substrates, were produced using the Physical Vapor Deposition (PVD) technique. Once Be was successfully deposited a film of 10.0 ±1.2 μm thickness was obtained. The roughness of substrates and of the beryllium film was determined, showing a mean value of 1.4 urn, 1.1 μm and 2.1 μm for Mo, W and Cu (ofhc) substrates, respectively. To study temperature effect on deposits, a thermal treatment was performed under brazing temperature conditions. Subsequently, deposits were characterized by means of different techniques including XR diffraction and Electron Microscopy (SEM).