Study Of Impact Resistance Of Polyurea Coated Glass Fiber Composite Plates

Glass fiber reinforced composites are widely used in the field of impact resistance due to their light weight and high strength,but due to their mostly laminated structure,they have a weak ability to resist large impact energy in the thickness direction;meanwhile,polyurea is a viscoelastic body with high elasticity and strong adhesion to metal,concrete and fiber composites,which has been applied in military and civil applications.In this paper,we will explore the impact resistance of polyurea-glass fiber composite plates to provide a new structural form for the impact resistance field,the results of the study can provide theoretical support for future applications of polyurea-coated glass fiber composite plates.Firstly,in this paper,the reliability of bonding performance between polyurea and fiberglass plates was verified by polyurea coating adhesion tests.A series of low-velocity impact tests were completed for polyurea-coated glass fiber composite plates.The impact resistance of polyurea-coated glass fiber composite plates was analyzed in terms of damage pattern,energy dissipation,maximum central deformation,and strain time course curve.The impact resistance of polyurea coated fiberglass composite plates was from excellent to poor for double-sided coating,back-elastic surface coating,and spring-face coating.Secondly,in this paper,the numerical model of low-velocity impact of polyurea-coated glass fiber composite plates was developed based on the experiments using Abaqus analysis software,and the numerical simulation results were compared with the experimental results to analyze the low-velocity impact mechanism of polyurea-glass fiber composite plate,and the influence law of impact bar shape on the impact resistance of composite plate and the impact resistance of composite plate under different combination methods were studied.Comprehensive analysis of the maximum central deformation,energy dissipation can be concluded that at an impact velocity of 18m/s,the back-elastic surface coating structure has the strongest impact protection against flat-head impact bars;the impact mechanical properties of the composite plate with polyurea as a sandwich layer are better than those of the composite plate with polyurea as a coating layer.Finally,this paper gives the influence law of four parameters,namely impact energy,glass fiber board thickness,polyurea coating thickness and glass fiber board strength,on the impact resistance of polyurea coated glass fiber composite plates based on the established numerical model.On this basis,the maximum central deformation was proposed as the damage index of composite plate,and the damage degree of polyurea coated glass fiber composite plate was qualitatively analyzed;the prediction formula of impact resistance of polyurea coated glass fiber composite plate under low velocity impact was established based on the damage index using multiple nonlinear regression method.