In this study, copper-boron carbide (Cu-B4C) metal matrix composites containing 5 wt%, 10 wt%, and 20 wt% of B4C were produced by powder metallurgy and characterization studies were carried out for the purpose of shielding nuclear wastes that emit high heat and radiation. Cu-B4C composites were obtained after 5 h of ball milling with a speed of 150 rpm, followed by uniaxial cold compaction at 500 MPa for 1 min, then sintering in a tube furnace at 900 ℃ for 1 h under argon atmosphere. The structural properties of the produced composites were investigated by X-ray diffraction (XRD), optical microscopy (OM), scanning electron microscopy (SEM), and energy-dispersive X-ray spectroscopy (EDX). In addition, microhardness and electrochemical corrosion tests of the produced composites were examined. Neutron absorbing properties of the samples were simulated by Monte Carlo particle transport program (MCNP), and experimentally tested in Am241-Be neutron source with an average energy of 4.5 MeV and a Canberra NP series BF3 gaseous neutron detector. From the obtained results, it was found that B4C particles were homogeneously distributed in the Cu matrix. With the increase of the B4C ratio in the composites, it was observed that the Vickers microhardness and the corrosion current values increased, and the thermal neutron shielding performance of the samples improved.
Anahtar Kelimeler: Cu-B4C composites, Powder metallurgy, Hardness, Electrochemical corrosion tests, Neutron shielding properties
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