Experimental study on crack irregularity of hollow shell particle under impact loading

Elucidating the morphology of impact cracks on the surface of walnut that is specific hollow shell particle is an effective way to reveal its fracture mechanisms. Unfortunately, there are few investigations about the morphology of impact cracks, especially crack irregularity. Thus, using image processing techniques and fractal theory, crack path roughness describing the tortuosity of crack path and crack branching coefficient characterizing sensibility to crack branch were used to quantify crack irregularities, respectively. The effects of walnut size and impact energy on crack irregularities were analyzed. The results show that fractal dimension could quantify crack irregularity. For crack path roughness, the effect of walnut size is larger than that of impact energy, whereas for crack branching coefficient, the effect of walnut size and impact energy are both significant. In addition, the relationship between crack path roughness and crack branching coefficient meets inverse function with exponential form according to energy conservation.

Automated summary

Elucidating the morphology of impact cracks on the surface of walnut is essential for understanding its fracture mechanisms. This study used image processing techniques and fractal theory to quantify crack irregularities, represented by crack path roughness and crack branching coefficient. The effects of walnut size and impact energy on crack irregularities were analyzed, showing that fractal dimension can effectively quantify crack irregularity. Additionally, the relationship between crack path roughness and crack branching coefficient follows an inverse exponential function based on energy conservation.