Short communication: Effect of Sn on the formation of -component dislocation loops in Zr alloys: In situ ion irradiation studies and atomistic simulations

The effect of Sn on the formation of -component dislocation loops was investigated by the combination of in situ ion irradiation and density functional theory calculations. The size of -component dislocation loops in Zr-1Nb-1Sn is smaller than that in Zr-1Nb, whereas the number density in Zr-1Nb-1Sn is about three times that in Zr-1Nb. We demonstrate that alloying Sn in Zr can decrease vacancy formation energy to impact the thermal stability of 〈c〉 loops and enhance vacancy diffusional anisotropy to inhibit the loop growth by promoting vacancy diffusion along the basal plane and reducing vacancy diffusion along the non-basal plane.