Study on the Mechanical Properties and Corrosion Behaviors of Fe-(20, 45) wt% Gd Intermetallics

45 wt%) Gd intermetallics were vacuum arc melted as the mother alloy of a neutron shielding and absorbing material.The structure of the cast Fe-20 wt% Gd intermetallics had primary dendrites with a short width of about 2 μm, which became coarse with increasing Gd content.The final compositions of the Fe-20 wt% Gd and Fe-45 wt% Gd intermetallics determined by Rietveld refinement were mainly Fe3Gd with 26.6 at% Fe2Gd, and Fe3Gd with various intermetallics like 13.9 at% Fe2Gd, 7.3 at% Fe9Gd and 3.9 at% Fe17Gd2, respectively.The micro-hardnesses, yield strength, ultimate compressive strength and elongation of the Fe-20 wt% Gd intermetallics were 629±12 Hv, 753 MPa, 785 MPa and 4%, respectively, and those of the Fe-45 wt% Gd intermetallics were 741±13 Hv, 772 MPa, 823 MPa and 3%.Passivity was not present in artificial sea water at room temperature.The corrosion potentials and the corrosion rates of the Fe-20 wt% Gd and Fe-45 wt% Gd intermetallics were -624 mVSHE, 2.771 mA/cm 2 , and -804 mVSHE, 3.397 mA/cm 2 , respectively.The corroded surface of the Fe-Gd intermetallics contained corrosion products like gadolinium with iron, which detached to leave a trail of pits.