PSI - Issue 13

Reza Khadem Hosseini / Structural Int grity Procedia 00 (2018) 00 – 000

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Reza Khadem Hosseini / Procedia Structural Integrity 13 (2018) 232–237

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Fig. 3. The optical micrographs of the specimens in the adjacent areas to the opening; (a) sample 1, (b) sample 2, M: martensite, F: ferrite, C: carbide.

The microstructures of samples in the opposite side of the opening, namely 3 and 4 presented in Fig. 4, were normal ferrite (F) and pearlite (P). In Fig. 5a, SEM micrographs of specimen 2, from the near area to the opening, reveals martensite islands (M) in a ferritic matrix (F) and also few carbides near the grain boundaries (C). However, Fig. 5b showing SEM micrographs of specimen 4, from the opposite side of opening, presents microstructures consisted of ferrite (F) and perlite (P).

Fig. 4. The optical micrographs of the specimens in the opposite side of the opening; (a) sample 3, (b) sample 4, P: perlite, F: ferrite.

Fig. 5. The SEM micrographs of the specimens 2 and 4, in the; (a) adjacent to opening, (b) opposite side of the opening; M: martensite, F: ferrite, P: perlite, C: carbide.