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REPORT DATE (DD-MM-YYYY)July 2016
ARL-TR-7723
SPONSORING/MONITORING AGENCY NAME(S) AND ADDRESS(ES) 10. SPONSOR/MONITOR'S ACRONYM(S)
SPONSOR/MONITOR'S REPORT NUMBER(S)
DISTRIBUTION/AVAILABILITY STATEMENTApproved for public release; distribution is unlimited.
SUPPLEMENTARY NOTES
ABSTRACTThis report presents a numerical model that captures various aspects of ballistic behavior of ultra-high-molecular-weight polyethylene, such as ballistic limit V50, back-face deformation (BFD) profile, remaining thickness of intact material, and interior delamination. The roles of fiber tension/shear and crush failure were investigated using a finite element model. Delamination due to matrix material failure at the interface between adjacent layers was investigated using a tiebreak contact algorithm. Parametric analyses were carried out to identify sensitive parameters that affected the material response to ballistic loading conditions. The results suggest that better helmet material needs to have higher interlaminar tensile strength, transverse Young's modulus, and crush strength and smaller transverse shear modulus and damage softening parameters. The parametric study also indicated that higher in-plane shear modulus resulted in lower V50 and lower BFD. A set of material parameters was identified that best fit the V50, BFD profile, remaining thickness of intact composites, and delamination failure observed in the experiments. Approved for public release; distribution is unlimited.
SUBJECT TERMSiii