The phase field method integrates the Griffith theory and damage mechanics approach to predict crack initiation, propagation, and branching within one framework. No crack tracking topology is needed, and complex crack shapes can be captures without user intervention. In this paper, a detailed description of how the phase field method is implemented with explicit dynamics into LS-DYNA is provide...

In this paper, the present investigation has been conducted keeping in mind some of the problems concerning the crack propagation direction and growth under constant loading in an inclined crack geometry. The present studies mainly focused on the development and modifications in the crack growth criterion to account the biaxial, shear loading and number of stress terms. Existing criteria for th...

Fatigue tests have been conducted on an advanced disc Ni-based superalloy (Low Solvus, High Refractory (LSHR) alloy) at 650 C in air under three-point bend loading to investigate the role of orientation-dependent grain boundary oxidation in crack initiation and early propagation. It is found that crack initiation occurs mainly from bulged grain boundary oxides, and cracks then predominantly pro...

Plate impact experiments are conducted to study the dynamic fracture processes in 4340 VAR steel which occur on submicrosecond timescales. These experiments involve the plane strain loading of a planar crack by a plane tensile pulse with a duration of approximately 1 /xs. The loading is achieved by impacting a precracked, disk-shaped specimen by a thin flyer plate. Motion of the rear surface of...

The welding heat input has a great influence on the weldments properties. This paper describes the influence of welding heat input on the weld metal toughness of high-carbon steel surface welded joint. The steel is surfaced with self-shielded wire, with three different heat inputs (6.5; 10.5 and 16 kJ/cm). Total impact energy, as well as crack initiation and crack propagation energies, are esti...

The phenomenon of fatigue in gears at the tooth root can be a cause of catastrophic failure if not detected in time. Where traditional low-frequency vibration may help in detecting a well-developed crack or a completely failed tooth, a system for early detection of the nucleation and initial propagation of a fatigue crack can be of great use in condition monitoring. Acoustic emission is a poten...

New generation jet engines are subject to severe reduced fuel consumption requirements. This usually leads to thin components in which damage issues such as thermomechanical fatigue, creep and crack propagation can be quite important. The combination of stresses due to centrifugal loads and thermal stresses usually leads to mixed-mode loading. Consequently, a suitable crack propagation tool mus...

This paper explores the fracture process based on finite element simulation. Both probabilistic and deterministic methods are employed to model crack initiation, and several commonly used criteria are utilized to predict crack growth. It is concluded that the criteria of maximum tensile stress, maximum normal stress, and maximum Mises stress, as well as the Coulomb-Mohr criterion are able to pr...