Study of solute segregation behavior at carbide–ferrite interfaces in 16MND5 welds

•A higher P segregation level at cementite-ferrite interfaces than M2.0-3.2C carbide–ferrite interfaces.•No influence of the intergranular carbides on solute segregation behavior at the vicinal GBs (within the first tens of nm from carbides).•A higher P segregation at the intersection region between carbide and GB.•The RES mechanism of P at carbide–ferrite interfaces after ion irradiation.