Inverse problems of inhomogeneous fracture toughness using phase-field models

Fracture toughness of dental composites determined using the short-rod fracture toughness test.

Plane strain fracture toughness (KIC) has been evaluated for a number of commercially-available dental composites. A modified Short-rod Fracture Toughness (SRFT) specimen design has been used, enabling small specimens to be tested conveniently. The effect on KIC of aging in water at 37 degrees C for seven days, one month, and six months has been determined for conventional, microfilled, and hyb...

Phase-field models for free-boundary problems

Phase-field models are very attractive in view of their numerical simplicity. With only a few lines of code, one can model complex physical situations such as dendritic growth. From this point of view, they constitute very interesting tools for teaching purposes at graduate level. The main difficulty with these models is in their formulation, which incorporates the physical ingredients in a sub...

Fracture toughness of graphene.

Perfect graphene is believed to be the strongest material. However, the useful strength of large-area graphene with engineering relevance is usually determined by its fracture toughness, rather than the intrinsic strength that governs a uniform breaking of atomic bonds in perfect graphene. To date, the fracture toughness of graphene has not been measured. Here we report an in situ tensile testi...

Laws of crack motion and phase-field models of fracture

Recently proposed phase-field models offer self-consistent descriptions of brittle fracture. Here, we analyze these theories in the quasistatic regime of crack propagation. We show how to derive the laws of crack motion either by using solvability conditions in a perturbative treatment for slight departure from the Griffith threshold, or by generalizing the Eshelby tensor to phase-field models....

Fracture Toughness of Metal Castings