Irradiation resistance of a novel multi-component Nb alloy at elevated temperature.

With the rapid development of nuclear industry, advanced niobium alloys with high strength and irradiation resistance are urgently required. In this work, a new multi-component Nb 80 Mo 10 Zr 10 Cr 10 Al 5 B 0.1 alloy has been designed, and the yield strength in compression can reach ∼1100 MPa, and plastic strain is ∼11.3%. To reveal the irradiation damage mechanism, both the NbMoZrCrAlB alloy and pure Nb samples have been irradiated by Xe ion at 350 °C and 750 °C, with the fluence of 2.1 × 1015 ions/cm2. The average diameter of Xe bubble under 750 °C irradiation is only ∼2.92 nm in NbMoZrCrAlB alloy, which is smaller than that of pure Nb (∼ 9.22 nm). Consequently, the volume swelling ratio is only 0.04% in NbMoZrCrAlB alloy, which is largely lower than that of ∼0.65% in pure Nb. Meanwhile, both the average diameter and number density of dislocation loops in NbMoZrCrAlB alloy are obviously decreased compared with pure Nb at the same irradiation temperature. This result should arise from the severe lattice distortion and sluggish diffusion in present NbMoZrCrAlB alloy, which is similar with the high entropy alloy. The present work provides a reference for designing novel Nb based alloys for advanced nuclear materials. [Display omitted] • The yield stress of the novel Nb alloy can reach ∼1100 MPa. • The novel Nb alloy shows a low swelling(0.04%) at elevated temperature irradiation. • The novel Nb alloy shows a distinct decrease in number density of dislocation loops compared with pure Nb. [ABSTRACT FROM AUTHOR]