Issue 20

A. Borruto et alii, Frattura ed Integrità Strutturale, 20 (2012) 22-31; DOI: 10.3221/IGF-ESIS.20.03 29 Figure 19 : SEM analysis. Porous particles from the surface crust – 700 X. Figure 20 : SEM analysis. Channels in the surface crust – 170 X. C Na Si S Cl Ca Fe Pt 1 93.25 5.75 1.00 Pt 2 95.59 3.81 0.60 Pt 3 88.17 1.34 0.19 5.02 2.15 0.50 2.63 Table 3 : EDS analysis (weight%) of areas shown in the Fig. 20. Si S Cl Fe Pt 1 7.48 45.50 14.17 32.85 Pt 2 31.66 68.34 Figure 21 : SEM analysis. Compacted particles from the surface crust – 170 X. Table 4 : EDS analysis (weight%) of areas shown in the Fig. 21. D ISCUSSION AND CONCLUSIONS he high corrosion resistance of Fe-Cr-Mo alloys has been ascribed to the rapid formation of a uniform, highly protective passive film [11]. The pipe’s hardness and resistance to various forms of corrosion are determined by the composition of the passive film (oxide layer) and play an important role in determining the lifetime of these T