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Four kinds of Pb-Mg-Al alloys with Al contents of 0, 5, 10, and 15% (mass fraction) were prepared by induction melting. The corrosion behaviors of these four alloys were investigated by electrochemical measurements and immersion tests. The results indicate that Mg, Mg17Al12, and Mg2Pb phases in Pb-Mg-Al alloys form a microgalvanic cell between Mg2Pb and Mg in corrosive solution. The corrosion of Pb-Mg-Al alloys begins from corrosion at α-Mg. The volume fraction and distribution of Mg17Al12 in alloys significantly affect their corrosion resistance. The increasing volume fraction and continuous distribution of Mg17Al12 with the increase of Al content led to a better corrosion resistance. The Pb-Mg-Al alloy with 10% Al shows the best corrosion resistance.

The new type of Pb-B shielding alloys with high tensile strength and hardness were prepared by casting. The microstructure and morphology of the Pb-B alloys were investigated by scanning electron microscope (SEM) analysis. Mechanical properties and radiation shielding effect of the alloys were compared with other Pb-based shielding alloys. The results indicate that the tensile strength and hardness increased up to 116 MPa and 160 HB with the 1.0 wt.% content of B. The fractographic examination conducted by SEM indicate that the Pb-B alloys are in form of plastic fracture, and the fracture model changes from the dimple to the intergranular quasi-cleavage with the increasing of B content. Furthermore, the composites are of the excellent shielding properties. Especially at the thickness of 20 mm, the shielding ratios for γ-ray and neutron reach 49.7% and 92.7%, respectively.

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