Issue 77

M. Al Khazali et alii, Fracture and Structural Integrity, 77 (2026) 56-70; DOI: 10.3221/IGF-ESIS.77.05

Reduction [%]

Reduction [%]

σ a [MPa] N =100,000

σ c [MPa] N c = 10,000,000

Condition









acr 1 σ / σ 

*100

acr 1 σ / σ 

*100

aref

aref

Reference specimens Corroded for 3 (35°C) days Corroded for 6 (35°C) days Corroded for 6 (35°C) + 3 (50°C) days

247

-

214

-

204

17.5

176

17.7

182

26.4

135

36.9

164

33.8

92

57.0

Table 6. Fatigue Resistance Reduction. The quantitative reduction in fatigue resistance for the investigated corrosion conditions is summarized in Tab. 6. The results indicate:  Corroded for 3 days: reduction of approximately 17.7% at 10 ⁷ cycles and 17.5% at 10 ⁵ cycles.  Corroded for 6 days: reduction of 26.4% at 10 ⁵ cycles and 36.9% at 10 ⁷ cycles.  Corroded for 6+3 days: the most severe degradation with 33.8% reduction at 10 ⁵ cycles and 57.0% reduction at 10 ⁷ cycles. These results confirm that fatigue degradation increases significantly with corrosion exposure time. The relationship between corrosion damage and fatigue resistance is further illustrated in Fig. 12, which shows the correlation between corrosion mass loss and normalized endurance limit derived from the Basquin model. The endurance limit of corroded specimens is normalized by the corresponding endurance limit of the uncorroded reference specimens.

Figure 12. Relationship between corrosion mass loss and normalized endurance limit of S460NL steel derived from Basquin’s law.

As shown in Fig. 12, the normalized endurance limit decreases approximately linearly with increasing corrosion mass loss. This trend demonstrates that corrosion-induced surface damage plays a dominant role in reducing the fatigue resistance of S460NL steel.

C ONCLUSION

his study investigated the influence of corrosion damage on the fatigue behavior of S460NL high-strength steel using experimental fatigue testing combined with statistical modeling. The findings indicate that corrosion exerts a substantial deleterious effect on fatigue resistance. The reference specimens demonstrated the highest fatigue performance, while specimens subjected to accelerated corrosion environments exhibited a progressive decline in fatigue life. T

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