A methodology for hydrocode analysis of ultra-high molecular weight polyethylene composite under ballistic impact

Abstract

Ballistic performance analysis of ultra-high molecular weight polyethylene (UHMW-PE) is critical for the design of armour systems against ballistic threats. However, no validated modelling strategy has been published in literature for UHMW-PE composite that captures the penetration and damage mechanisms of thick targets impacted between 900 m/s and 2000 m/s. Here we propose a mechanistically-based and extensively validated methodology for the ballistic impact analysis of thick UHMW-PE composite. The methodology uses a non-linear orthotropic continuum model that describes the composite response using a non-linear equation of state (EoS), orthotropic elastic plastic strength with directional hardening and orthotropic failure criteria. A new sub-laminate discretisation approach is proposed that allows the model to more accurately capture out-of-plane failure. The model is extensively validated using experimental ballistic data for a wide range of UHMW-PE target thicknesses up to 102 mm against 12.7 mm and 20 mm calibre fragment simulating projectiles (FSPs) with impact velocities between 400 m/s and 2000 m/s. Very good overall agreement with experimental results is seen for depth of penetration, ballistic limit and residual velocity, while the penetration mechanisms and target bulge behaviour are accurately predicted. The model can be used to reduce the volume of testing typically required to design and assess thick UHMW-PE composite in ballistic impact applications

Finite element modelling of Dyneema® composites: From quasi-static rates to ballistic impact

“…Ultra-high molecular weight polyethylene (UHMWPE) fibre composites are increasingly being used in impact scenarios due to their extremely high specific tensile strength and stiffness [1]. Capturing the material behaviour through numerical modelling techniques over a range of loading conditions provides the prospect of being able to predict current performance for use as a design tool, and also provide insight into the complex deformation and failure mechanisms observed during highspeed impact [2,3] that can be difficult to fully capture analytically [4]. Several dimensional hierarchies exist within UHMWPE composites, with the scale of modelling used being dependent on a trade-off between the detail of phenomena required to be captured and the computational expense.…”

“…Nguyen et al [3,14] recently advanced this model to better capture the ballistic limit and BFD by using a sub-laminate approach, with sub-laminates separated by tied contacts in order to represent delamination.…”

High-Velocity Impact Performance of Aluminum and B4C/UHMW-PE Composite Plate for Multi-Wall Shielding

“…The non-linear orthotropic material model (Ortho model) developed in [20][21][22][23] is used for modeling the UHMW-PE composite. The material model includes orthotropic coupling of the material volumetric and deviatoric response proposed by Anderson et al [24], the non-linear equation of state and orthotropic hardening proposed by Chen et al [25], the stress-based composite failure criteria, and the orthotropic energy-based softening [26]. For the equation of state, the pressure is defined by…”

“…All of the UHMW-PE composite material parameters are given in Table 4. [26] In the simulation analysis, the quarter model was applied to reduce calculation time. The projectile and the Al 7075-T651 bumpers were modeled using SPH coding with a smooth length of 0.5 mm.…”

Yarn-Level Modelling of Woven and Unidirectional Thermoplastic Composite Materials Under Ballistic Impact

“…Nevertheless, such approach was widely implemented both into finite element and into finite difference codes like ABAQUS, LS-DYNA, ANSYS AUTODYN etc. and used by many researchers to simulate ballistic impact onto ceramic/composite [6][7][8][9] or fully fibre composite armour [10][11][12][13][14][15][16].…”