Dynamic Response Of Carbon Fiber Reinforced Composite Laminates According To Impact Load

According to the excellent mechanical properties,composite laminates are widely used in aerospace,vehicles and ships.At the same time,the mechanical properties of composite laminates in the thickness direction are weak and sensitive to impact load.These impact loads are different in speed,material and mass,so the response of laminates is also different.In this paper,carbon fiber reinforced composite laminates are taken as the research object,and ice sphere and tungsten beads are used as impact objects to characterize the damage state and dynamic response of the composite laminates under the impact of brittle and rigid objects,and the differences between them are studied and analyzed.The research was carried out by combining experiment and simulation.According to the actual conditions,7g tungsten beads were used to impact the T800 / 3200-2laminates of 100mm*100mm,and 90 g ice spheres were used to impact the T800 /3200-2 laminates of 400mm*400mm.The high-speed camera method was used to obtain the velocity information of the impactor,the CT scan was used to obtain the damage information of the laminated plate subjected to tungsten beads,and the ultrasonic C scan was used to obtain the damage information of the laminated plate subjected to ice balls.On the basis of the test results and the theory of composite mechanics,the physical model was established in ABAQUS.The three-dimensional stress element and zero thickness cohesive element were used in the model.The three-dimensional stress element was used for tungsten bead and the smooth particle flow model was used for ice sphere.After the validity of the model is verified,the impact test conditions are simulated,and a numerical example is designed to analyze the influence of the impact mass and laminate ply direction on the damage of composite plates under the action of two kinds of impact bodies.In this paper,the difference of damage caused by two kinds of impact body is studied from two aspects of intralaminar damage and interlaminar damage:(1)In the aspect of intralaminar damage,in plane,the damage of the laminate under the action of w-bead is concentrated near the impact point,which is less affected by the velocity and less damaged at the restraint end.The damage of the restraint end of the laminate under the action of ice hockey is more serious.In the thickness direction,when the tungsten bead is the impact body,the damage increases gradually in the thickness direction,and the larger the initial kinetic energy is,the more obvious the trend is.When the ice ball is the impact body,the damage appears in the impact surface or specific layer in the thickness direction,and the main reason for this phenomenon is the damage at the constraint end.(2)In the aspect of interlaminar damage,the stiffness of the bonding layer changes little under the action of tungsten bead,and the delamination damage is concentrated near the perforation,which exists in every adjacent layer;The delamination projection area of the laminated plate impacted by the ball is greatly affected by the initial kinetic energy of the impact body,which first occurs in the middle layer.With the increase of the initial kinetic energy of the impact body,the delamination area gradually increases and gradually diffuses to other layers.At the same time,it is found that the dynamic response time of the laminated plate is longer under the action of ice hockey,and the collision completion time of ice hockey is more than 10 times of that of tungsten bead under the same kinetic energy.Kinetic energy is an important parameter to predict the damage degree of the target under the action of two kinds of impact bodies.The damage condition of the same impact body is basically the same under the action of the same impact kinetic energy,while the damage of the target under the action of different impact bodies is significantly different.With the increase of initial kinetic energy,the damage of the target will decrease when the tungsten bead is the impact body;When the ice hockey is an impact body,all kinds of damage increase with the increase of initial kinetic energy of the impact body.In addition,it is found that the ply direction has different effects on the damage caused by the two types of impact,and the damage of the laminates with orthogonal ply under high velocity impact is smaller than that of the laminates with two types of impact.