Muti-scale Analysis Of High-velocity Penetration Resistance Of Carbon Fiber Reinforced Magnesium Alloy Laminates

Fiber Metal Laminates(FMLs)are hybrid composites consisting of metal-alloy sheets and fiber reinforced composite layers.FMLs have been widely used in aeronautical and aerospace structures due to their high specific strength,high tolerance to fatigue and corrosive resistance.In this paper,to study the high-velocity impact behavior of FMLs,the dynamic damage constitutive model of each component material in the FMLs was firstly investigated and the finite element model of FMLs under high-velocity impact was established in ABAQUS/Explicit.The high-velocity impact behavior of carbon fiber reinforced magnesium alloy laminates was then studied.In addition,a representative volume element(RVE)model for graphene nanoplatelets(GNP)reinforced carbon fiber/epoxy composites(GNP/CF/epoxy)was established using a micromechanical method,and the mechanical properties of the composites were simulated.GNP effects on the impact response of carbon fiber magnesium alloy laminates was finally investigated.Firstly,the dynamic damage constitutive model of each component material in the FMLs and finite element model of FMLs subjected to high-velocity impact were established.The Johnson-Cook constitutive and failure model was used in metal layers.The surfaced-based cohesive behavior was utilized to describe the interlaminar failure,while for the unidirectional fiber-reinforced composite layer,the strain-based three-dimensional Hashin failure criterion was adopted.Meanwhile,the effect of strain-rate on composite modulus and failure strain was taken into accounted.A user-defined material subroutine was used to define the composite constitutive and failure model and was implemented in ABAQUS/Explicit.On this basis,the finite element model of FMLs subjected to high-velocity impact was established,and the accuracy of the finite element model was verified by comparing simulation predictions and existing experimental results.Then,the high-velocity impact behavior of carbon fiber reinforced magnesium alloy laminates was simulated using the developed finite element model.Based on published experimental data,the strain-rate effects of carbon fiber composites were investigated,and the variation law of material properties such as modulus and failure strain with strain rates was obtained.According to the results,the perforation process can be sub-divided into three stages and the damage area of composite layers under different damage modes was also analyzed.It is found that the matrix and fiber tensile damage is the main damage mode,followed by matrix compressive damage.The laminates of 3/2 structure and 2/1 structure were compared.The results show the ballistic limited velocity and specific perforation energy of laminates of3/2 structure are improved by 44.79% and 19.59%,respectively.The impact behavior of hybrid glass and carbon fiber reinforced magnesium-based(Mg-based)FMLs with different configurations was also studied.The results show that the damage area and impact resistance of the Mg-based hybrid laminates are between that of glass fiber composites and that of carbon fiber composites.Finally,the effects of GNP addition in epoxy resin on the mechanical properties of carbon fiber composites and the impact response of fiber magnesium alloy laminates were simulated.The GNP information was generated using Matlab,and the RVE model was established using Python in ABAQUS.The RVE model was validated by comparing simulation predictions with experimental tests in the reference.The failure process of the GNP/CF/epoxy composites under transverse tensile loading was subsequently analyzed,and the transverse and longitudinal tensile properties of composites with different GNP volume fraction were compared.The results show that GNP volume fraction has small effects on longitudinal tensile properties,but it affects significantly transverse tensile properties.The enhancement in transverse tensile strength is best when the GNP volume fraction reaches0.35 %,and the transverse tensile strength is improved by 18.49%.The high velocity impact behaviour of GNP reinforced magnesium-based carbon fiber metal laminates was studied.Compared with laminates without GNP,the ballistic limited velocity and perforation energy of laminates with GNP are improved by 10.22% and 21.49%,respectively.