Influence of surface tension on mode-I crack tip field

• We consider the influence of surface tension on mode-I fracture.
• Surface tension affects the elastic field and J-integral around crack tip.
• Surface tension has an enhancing effect on material toughness.

In the present paper, we address the influence of surface tension on the mode-I crack tip field, which is modeled as a curvature dependent normal traction acting along the crack surface. Through finite element simulations, we examine the stress field and the J-integral around the crack tip. It is found that when the curvature radius at the crack root reduces to nanometers, surface tension significantly alters the stress state near the crack tip. Surface tension leads to compressive stress along the symmetric plane and prominent shear stress adjacent to the symmetric plane. Moreover, surface tension decreases the J-integral and thus has a tendency to enhance material toughness. The sharper the crack root, the more significant the influence of surface tension.