Issue 73

V. Pisarev et alii, Fracture and Structural Integrity, 73 (2025) 108-130; DOI: 10.3221/IGF-ESIS.73.08

Impact dimple induced by hemispherical tip of 20 mm diameter The size of the hemispherical impactor and the impact energy were chosen so as to obtain a contact dimple with a diameter that is close in magnitude to that of a static indentation of a steel ball with diameter of 16 mm. Interference images visualized after probe hole drilling at point 1 of CP_D-20 coupon are presented in Fig. 7. The quality of the fringes leaves much to be desired, due to the significant degree of damage to the surface layers of the material. Thus, values of absolute fringe order differences can be only approximately counted as it is illustrated in Fig. 7. Note, however, that these differences have a negative physical sign as it takes place in statically induced case (see Fig. 5).

u N   –9.0

v N   –14.0

(a) Component u ,

(b) Component v ,

Figure 7: Specimen CP_D-20. Interferograms referred to point 1.

Interference images, obtained at various points in the vicinity of the contact dimple after drilling a through hole, are shown in Fig. 8

u N  = –9.0

v N  = +9.5

(a) Component u ,

(b) Component v ,

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