Formation of Ni–Si clusters and their relationship with dislocation loops in irradiated stainless steels

•Ni–Si clusters formed on loops were confirmed via shape, size, and orientation.•Si and Ni distribution in torus-shaped clusters was affected by loop stress field.•Si content of stainless steels did not change the composition of Ni–Si clusters.•The Ni/Si ratio in large clusters was almost constant and was between 1.6–3.0.