Research Summary
Penetration and Perforation Mechanics of Composites
Authors: Bazle Z. (Gama) Haque, and John W. Gillespie Jr.
OBJECTIVES
Identify different penetration phases and associated damage mechanisms for thick-section composite materials
Use LS-DYNA simulations to model penetration and perforation of composites utilizing the progressive composite damage model MAT162.
Investigate penetration damage mechanisms below and above the ballistic limit by observing the cross-section of the composite laminate at different times
Develop theoretical models for different phases of penetration
PENETRATION OR P-PHASE
Transverse matrix damage and delamination is observed around the depth of penetration cavity
No matrix cracking or delamination damage under the projectile
No visible dynamic deflection of the back face lamina


TRANSITION OR T-PHASE
Transverse matrix damage and delamination forms damage cone
Composite under and surrounding the projectile undergoes dynamic deformation


PERFORATION OR F-PHASE
The projectile and composite in contact move together with same particle velocity
Back face dynamic deflection reaches maximum at end of F-phase

RETRACTION OR R-PHASE
Particle velocity of last sub-laminate at the peak deflection becomes zero
Particle velocity reverses its direction of motion
Last sub-laminate and remaining laminates retract back

DEFORMATION DYNAMICS: P-T-F-PHASES

SUMMARY
Four penetration phases have been identified for finite thickness thick-section composites
Deformation mechanisms of each penetration phase have been identified which can be used to develop theoretical models of these penetration phases
ACKNOWLEDGEMENTS
This work is supported by the ARL-CMR and ARL-CART Programs