Issue 78

G. Palomba et alii, Fracture and Structural Integrity, 78 (2026) 233-247; DOI: 10.3221/IGF-ESIS.78.14

(a)

(b)

Figure 5: Digital Image Correlation strain maps during a tensile test of a welded specimen: (a) ε ₓₓ and (b) ε ᵧᵧ . It is also noteworthy that one welded specimen exhibited a distinctly different stress–strain profile, characterized by lower yield and ultimate strength values and an overall suppressed strain-hardening rate, as shown in Fig. 6, which reports the obtained true stress-strain curves, where true strain over time was calculated directly by DIC analysis, while the stress were converted according to equation   1 ln true eng      . While a localized microstructural defect (such as localized porosity or lack of fusion) could be responsible for this early plastic instability, further microscopic or radiographic analysis, which falls outside the scope of this minimally-destructive profiling methodology, would be necessary to confirm this interpretation and to definitively characterize its nature. Nonetheless, this curve is included to illustrate how the macro-tensile response captures local structural vulnerabilities.

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