Stress intensity factor dependence on anisotropy and geometry during micro-fracture experiments
Brinckmann, S. and Kirchlechner, C. and Dehm, G.
Volume: 127 Pages: 76-78
Miniaturized fracture beam experiments are often used to identify the fracture toughness of single phases and particular grain boundaries because large-scale experiments reveal only homogenized material properties. The evaluation of the microscale toughness is based on isotropic 2D models although the majority of materials are anisotropic. Moreover, the thickness influences the fracture toughness because the crack driving force is maximum in the beam center. This study quantifies the influence of anisotropy, Poisson's ratio and beam geometry using thousands of 3D simulations. We give guidelines for micro-cantilever design and quantify the changes in fracture toughness, if the guidelines cannot be fulfilled. © 2016 Acta Materialia Inc.