Mechanical property and irradiation resistance of high entropy pyrochlore (Sm0.2Eu0.2Gd0.2Y0.2Lu0.2)2Ti2O7

High entropy ceramics have recently attracted a lot of attention due to their superior physical properties. In this work, a novel high entropy pyrochlore (Lu0.2Y0.2Gd0.2Eu0.2Sm0.2)(2)Ti2O7 (HTP-1) was designed and prepared. Sample was characterized by X-ray diffraction, Raman spectroscopy and transmission electron microscopy coupled with an energy dispersive spectrometry. The results show that single-phase HTP-1 is successfully synthesized and exhibits severe lattice distortion. The Vickers hardness of HTP-1 measured by the microhardness tester is similar to 922.28 Hv, which is significantly higher than the result calculated with the mixture rule, demonstrating that high entropy pyrochlore has high mechanical hardness. In-situ TEM was performed on HTP-1 irradiated with 800 keV Kr2+ at room temperature to investigate irradiation resistance of sample. The critical amorphization dose of HTP-1 is 0.27 dpa, which indicates the irradiation resistance of HTP-1 is between Sm2Ti2O7 and Y2Ti2O7.