Issue 78

A. P. Soldatenkov et alii, Fracture and Structural Integrity, 78 (2026) 248-259; DOI: 10.3221/IGF-ESIS.78.15

In addition, the pattern of the fatigue curves changed significantly with increasing the aging temperature from 450 up to 520  C. A near linear increase in the number of cycles to failure was observed with decreasing the maximum stress in a cycle for heat treatment 1. For heat treatment 2, this dependence reflected the conventional fatigue limit typical for HCF regime for titanium alloys [27] at the maximum cycle stress of 800 MPa (Fig. 5).

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Figure 6: General views (SEM-micrographs) of the facture surfaces in the specimens (heat treatment 2) after the fatigue tests at 850 (a), 900 (b) and 1200 MPa (c) (the crack initiation regions are indicated by arrows), with a scheme (d) of the sequence of the formed fracture zones “1–3” with different reliefs, as well as examples of fracture surfaces with the boundaries of indicated zones in specimens tested at 850 (e) and 1200 MPa (f).

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