PSI - Issue 68

4

Rahul Singh et.al / Structural Integrity Procedia 00 (2025) 000–000

Rahul Singh et al. / Procedia Structural Integrity 68 (2025) 715–721

718

(c)

(a)

(b)

(d)

(e)

(f)

Fig 1: (a) TEM image of NP550 showing interlamellar spacing (b-c) SEM image of NP550 showing lamellar structure and colony size of pearlitic steel (d-f) EBSD image and nodule size measurement for NP550.

Table 1: Microstructure features size.

Ferrite lamella thickness in nm

Cementite lamella thickness in nm

True interlamellar spacing in nm

Colony size in µ m

Nodule size in µ m

Specimen

NP550

42.5 ± 3.4

4.5 ± 1.1

57.2 ± 2.3

6 ± 1.5

30 - 70