Particle modeling of polymeric material indentation study

This paper presents a further application of a newly modified particle modeling (PM) for the simulation of dynamic fragmentation of another polymeric material, vinyl ester, subject to an impact of a rigid indenter after the previous study of nylon-6, 6 [Wang G, Al-Ostaz A, Cheng AH-D, Mantena PR. Particle modeling of a polymeric material (nylon-6, 6) due to the impact of a rigid indenter. Comput Mater Sci [in press]]. A two-layer particle interaction scheme (nearest-second neighboring particle interaction) is still adopted to eliminate a mesh bias in the direction of fracture propagation in a regular lattice model with uniform axial linkage technique. The effective bond stiffness with this new interaction network is addressed to preserve the associated material's physical property, i.e., Young's modulus. The modeling results compare favorably with the according experimental observations, in terms of the time-dependent load and energy profiles, the deflection value at the peak of the load, and the indenter drop speed versus time, etc. Failure strain is found to be a critical factor affecting the prediction accuracy. Via this study, it exhibits again that particle modeling can be used as an alternative tool for dynamic fracture problems.