On the development of a relation between fractal dimension and impact toughness

Fractal characterization is an increasingly important method in fractography. This paper presents the results of a study made on the relation between the fractal dimensional increment (Df′), as measured by the slit island technique, and the impact toughness in a commercial medium-carbon ferrite-pearlite steel. Charpy V-notch samples with different thermomechanical treatments were tested at room temperature and demonstrated a positive relation between Df′ and the impact energy. This study includes consideration of fracture micromechanism factors for which Df′ cannot always be positively related to the toughness.