PSI - Issue 54

Robin Depraetere et al. / Procedia Structural Integrity 54 (2024) 172–179 R. Depraetere et al. / Structural Integrity Procedia 00 (2023) 000–000

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Fig. 5: The aspect ratios of all scanned specimens averaged per equivalent diameter D eq .

Fig. 6: The cumulative void distribution of all scanned specimens, weighted based on the volume of each individual void.

To quantify the void size distribution, the cumulative void distribution versus the equivalent diameter D eq of each sample is visualised in Figure 6. Note that the void distribution is weighted based on the volume V of each void. A comparison between the uncharged and the hydrogen charged specimens reveals that the void distribution remains relatively una ff ected by the presence of hydrogen.

4. Discussion

In general, the significant number of voids observed in the samples after fracture is likely related to the vintage manufacturing process that was used for producing the steel. This led to a large amount of impurities (as can be derived from the sulfur and phosphorus content in Table 1), which is correlated to the process of void nucleation [Wcis´lik and Pała (2021)].