PSI - Issue 75

11

D. Jbily et al. / Procedia Structural Integrity 75 (2025) 158–175 Author name / Structural Integrity Procedia (2025)

168

REF Pinion

SP Pinion

Fig. 13. Band contrast map of worn areas in the tooth dedendum. An example of the microstructure in band contrast imaging (crystalline structure fraction) is shown in Fig. 13, Erreur ! Source du renvoi introuvable. near the subsurface of the tooth surface in worn areas. Significant decreases in crystallinity (work hardening) are observed at a depth of approximately 5 to 10 µm for both cases. This microstructural change near the surface is not uniform. Very dark areas (with very low indexing) are observed, indicating a nearly amorphous structure. The boundary between this affected zone and the subsurface is marked by a crack reaching the surface, particularly in the SP case (see Fig. 14, Fig. 15). However, in adjacent surface areas, finer grains are observed, suggesting the possibility of recrystallization at the extreme surface.