Study on Applicability of Phase Field Method in Quasi-Static Fracture Behavior Simulation of PBX Components

Abstract

Crack in polymer bonded explosive (PBX) components will influence the safety and reliability of weapon system. In order to accurately simulate the quasi-static fracture behavior of PBX components, the quasi-static arc Brazilian experiment of PBX explosive was carried out first. Then, the phase field method (PFM) and the traditional extended finite element method (XFEM) are used for the comparative simulation of the arc Brazil test process, in which both the maximum principal stress and the maximum principal strain initiation criterion are used in XFEM simulation. The calculation results show that the relative error of failure load calculated by PFM is small (less than 1%), while the error of XFEM calculation is large (the error of strain criterion and stress criterion are -61% and 42% respectively). Meanwhile, the fracture initiation locations calculated by PFM are located at 1/4 and 3/4 away from the end face of the Brazilian sample, which is in good agreement with the experimental results. In addition, PFM avoids the problems of crack mutation and discontinuity in XFEM. The results show that the PFM can accurately calculate the quasi-static fracture behavior of PBX components.