Research On High Velocity Oblique Impact Damage Of Composite Laminates

With the expansion of application fields of composite material, research on composite mechanicalproperties has become one of the hottest research topics in aviation industry. Among all mechanicalproblems of composite, under high velocity impact damage problem, especially problems of highvelocity oblique impact, was complicated and much harder to deal with because of its rate-dependentconstitutive equation. In this paper, a numerical analysis model for problems of high velocity obliqueimpact on fiber reinforced composite was established based on3D nonlinear dynamic finite elementanalysis by using Finite Element Analysis Software ABAQUS. Based on this model, research wasmade on ballistic property and laminates damage property of composites under high velocity obliqueimpact of rigid projectile.Firstly, According to the macroscopic and microscopic structure of composite laminates, arate-dependent constitutive equation for composite laminates was deduced by assuming fiber as linearelastic rate-independent and assuming matrix as viscoelastic. Cohesive elements were introduced intolayers to simulate delamination and3D-Hashin failure criteria are used to predict in-plane damage forstiffness reduction. Furthermore, a3D rate-dependent Continuum Damage constitutive Model (CDM)was established for modeling high velocity oblique impact problem of fiber reinforced compositelaminate.Secondly, based on CDM, problems of composites damage under high velocity oblique impact ofrigid projectiles were simulated. The whole process of penetration, pierce and damage of compositelaminates was studied under different entering angles and impact velocities and detailed discussionswere made on the influence of entering angles and impact velocities on impact results.Lastly, based on numerical analysis, influence of boundary stress condition on anti-bullet propertyof composite was studied. Damages of laminates under different boundary stress conditions anddifferent impact velocities were simulated and discussions were made on the influence of boundarystress and impact velocities on impact results in detail.