On Fracture Criterion of Titanium Alloy under Dynamic Loading Conditions

One of the most important factors in ensuring the a dequacy of the mathematical modeling of limiting states of structures is the choice of the material local fracture criterion and accurate determination of its parameters. The paper discusses some traditional ap proaches to the construction of local failure crite ria of metals under dynamic loading, methods of their p arameters identification, as well as the developmen t of these approaches on the example of impact penetr ation problem. The work focuses on the possibility of modeling viscous and brittle types of fracture with in a single deformation type criterion, while the dependence of fracture strain on the stress triaxia lity ratio can became complicated and nonmonotonic. The quality of the considered criteria is determine d by comparing the results of virtual simulation wi th the data of full-scale experiments that implement v arious types of stress state and failure mechanisms . The results of full-scale and virtual compression, tension and penetration dynamic tests of the titani um alloy samples are given. Virtual experiments were cusing nonlinear LS-DYNA® code.