Phase transition behaviour and properties of Ti-Gd based thermal neutron shielding alloys

• α-Ti was stabilised by Gd, equiaxial α in Ti-xGd transforms to lamellar α at 1000 °C. • Alloy slip was impeded by Gd precipitation during plastic deformation of alloys. • The mechanical properties of Ti-5Gd are good with elongation up to 19.2% The phase transition behaviour and properties of Ti-Gd based alloys were investigated. The addition of Gd increases the α/β phase transition temperature of titanium alloys. The equiaxial α-phase in Ti- x Gd alloys transforms into lamellar α-phase from 800 °C to 1000 °C. The addition of Fe element reduces the α/β phase transition temperature, and the α + β → β transition in Ti-7.5Fe- x Gd alloys at temperatures between 600 °C and 800 °C. Gd elements precipitated as a second phase and alloys slip were impeded by the Gd phase during plastic deformation. The Ti-5.0Gd alloy exhibited good mechanical properties, with tensile strengths exceeding 500 MPa and elongation reaching up to 19.2 %. In addition, as the gadolinium content increases, there is a significant decrease in thermal neutron transmittance. When the alloy thickness is 0.07 cm, the shielding efficiency of the Ti-10.0Gd alloy for neutrons with an energy of 0.025 eV approaches 100 %. This indicates that the material exhibits excellent mechanical properties and effective thermal neutron shielding capabilities.