A three-dimensional validation of crack curvature in muscovite mica

Experimental and computational efforts focused on characterizing crack tip curvature in muscovite mica. Wedge-driven cracks were propagated under monochromatic light. Micrographs verified the subtle curvature of the crack front near the free surface. A cohesive approach was employed to model mixed-mode fracture in a three-dimensional framework. Finite element calculations captured the crack curvature observed in experiment.