PSI - Issue 82

L.F. Guedes et al. / Procedia Structural Integrity 82 (2026) 199–205 Guedes et al. / Structural Integrity Procedia 00 (2026) 000–000

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Fig. 3. SEM images of specimens (a) N350, (b) N400 and (c) N570.

(a) (c) Fig. 4. SEM images of specimen N570 (a) Nitrided layer, subdivided in two sub-layers; (b) External sub-layer; (c) damage and intergranular attack in the internal sub-layer. Embrittlement indexes (R e Total , R e Unif , RA s x e ) were calculated dividing the ductility ( e Total and e Unif ), and toughness (A s x e ) of the nitride specimens (-N) by the same parameters measured in the specimens which were not nitrided (-C): !"#$% = & !"#$%&' & !"#$%&( (1) '()* = & )*+,&' & )*+,&( (2) +,& = - -./&' - -./&( (3) (b)

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Fig. 5. Tensile curves: (a) N350; (b) C350.