Study On Explosion Response And Ballistic Performance Of Thermoplastic Fiber Reinforced Metal Laminates

Fiber-metal laminates(FMLs)are super-hybrid composite structures composed of fiber-reinforced composite materials with high-strength and thin metal layers that are alternately laminated at a certain temperature and pressure.FMLs inherits the advantages of metal and fiber-reinforced composite materials and effectively compensates for the deficiencies of them.The presence of the metal layer plays a protective role on the composite material layer,so that the FMLs has excellent mechanical properties.Based on various considerations such as mechanical properties,anti-shock properties and lightweight construction,the thermoplastic-based fiberreinforced metal laminate structure has unique advantages in ship protection structure.This paper takes thermoplastic fiber-reinforced metal laminates as the object,and conducts experimental and numerical simulations on the confined blast load and projectile impact encountered by the laminates.The main contents include:(1)Considering the complexity of the confined blast loading itself,the investigation on characteristics of the confined blast load was firstly carried out.Numerical simulations and analysis of the metal plate subjected to the confined blast loading were performed,based on which the empirical formula of the saturation response time of the confined blast loaded structure and the recommended value range of the dimensionless parameter λ were proposed.Experimental tests of the confined blast load from different masses of charges were carried out,and the empirical formula for predicting the deflection of plates was obtained,in which the influence of the combustion of detonation products on the total energy release and the subsequent dynamic response of the structure was considered.In addition,numerical simulations were further performed carried out according to the experiment procedure,and the reliability of the numerical method was verified.(2)Experimental and numerical studies on the dynamic response of thermoplastic fiber-reinforced metal laminates subjected to confined blast load were carried out.The dynamic response histories of the laminate and three basic failure modes of the internal fiber damage were obtained.According to the meso-geometric parameters of the fiberboard,the representative volume element method was employed to calculate the mechanical properties,which were used as input parameters for the simulations.The experimental cases of the laminate response under confined blast load were simulated and analyzed.The relative error between the calculations and the experimental results was within 10%.(3)Numerical studies of the response of fiber-reinforced metal laminates subjected to projectile impact were performed.Compared with experimental observation and results,a numerical model for calculating the impact response of laminates impacted by a projectile was established and verified.Based on the verified numerical model,a parametrical analysis was performed.A series of 100 cases were calculated with different parameters.The analysis studied the influence of varied projectile shape,the impact positions,and the different impact angles of the projectile on the response.In addition,the interlaminar strength of the laminates and the thickness ratio of different components have been analyzed.The results show that for the determined total thickness of the FMLs,varied thickness distribution of different layers will achieve a higher energy absorption.(4)The response of thermoplastic fiber-reinforced metal laminates subjected to the coupling loads of projectile impact and confined blast load was investigated.Firstly,the load characteristics of cased charge in a confined space were analyzed,and the empirical formula of the equivalent bare charge based on the deformation of the target plate was obtained.Based on the response characteristics of laminates under confined blast loading and projectile impact loading,a coupling method of projectile-shock wave was proposed by employing the ballistic limit and saturation response time as variables.Simulation results show that when the projectile arrives in the duration of saturation response,the damage would be more severe.