Heavy ion irradiation response of an additively manufactured 316LN stainless steel

•Response of solidification cellular structures in an additively manufactured 316LN SS was investigated under annealing and heavy ion irradiation at 450 ˚C.•Effects of cellular structures on the formation of Frank loops were studied.•Cr depletion, Ni and Si enrichment along the cellular walls were first observed in irradiated additively manufactured 316LN SS.•Experimental results were interpreted by a comparison with previous neutron irradiation studies on wrought 316L and 316LN SSs.