A Basic Study of Stop Hole to Prevent Brittle High-Speed Crack Propagation : 2nd Report, Discussion of Crack Restart Condition Using the Moving Finite Element Analyses

Abstract

The stop hole is one of the crack arrester systems, which is used to prevent the growth of fatigue cracks. However, the stop hole is not expected to prevent high-speed crack propagation. Because the mechanical condition of fast crack propagation behavior near the stopping hole is not cleared, the criterion of the stop for brittle fracture is not established. In this study, authors focus re-propagation start (restart) condition of crack from the stop hole. To discuss the restart condition of high-speed crack propagation, experiment observation and finite element analysis result are compared. In the numerical simulation, dynamic crack propagation simulations are carried out, using the moving finite elememt method based on Delaunay automatic triangulation. The various parameters are calculated from the numerical results.