Study On Impact Properties Of Graphene/Polyurethane And Its Ceramic Ball Composite Structure

Polyurethane elastomer,the core layer is usually used as in composite structure,determines the mechanical properties and application scenes of composite structure largely.The use of particle re inforced polyurethane elastomer is the focus of research at home and abroad.In this paper,graphene is selected as the reinforcing phase and filled into polyurethane elastomer,and the effect of graphene content on the mechanical properties of polyurethane elastomer is discussed.Then,the impact resistance characteristics of CPU,GO/CPU and GO/CPU/CB are studied by experiment and numerical simulation.The main research contents of this paper are as follows:Polyurethane elastomers and three graphene/polyurethane elastomers with different graphene contents were prepared,and the quasi-static mechanical properties of four elastomers were tested,and the effects of graphene content on tensile strength,elongation and compressive stress-strain of polyurethane elastomer were discussed.When the content of graphene is 0.4wt%,the integral mechanical properties of polyurethane elastomer is best.The dynamic mechanical properties of graphene/polyurethane elastomer under large deformation were studied by using the SHPB improved,and the results show that the dynamic compressive stress-strain curve of polyurethane elastomer shows obvious rate-dependent.Combined with the test results of static compression and dynamic compression,a trinomial constitutive model considering strain rate is established and verified.In addition,the relationship between glass transition temperature and impact velocity of graphene/polyurethane elastomer was also explored by DSC test method.Three composite structures of CPU,GO/CPU and GO/CPU/CB were prepared,and the penetration test device is used to study the mechanical behavior of three kinds of composite structure against spherical-nosed projectile penetration.The penetration mechanical properties include the value of limited velocity,the law of velocity increments,energy absorption efficiency,and the failure modes and differences of the three structures under different initial velocities.And the influence of graphene and ceramic ball on the penetration resistance of the composite structure is discussed.The results show that compared with the CPU composite structure,the mass of GO/CPU increases by 0.4%,the ballistic limit speed increases by 5.86%,the mass of GO/CPU/CB increases by 20.33%,and the ballistic limit speed increases by20.09%.With the increase of the initial velocity of the projectile,the velocity change decreases obviously,and the energy absorption rate of the structure decreases gradually.The simulation models of GO/CPU and GO/CPU/CB composite structures are established by LS-DYNA.The accuracy of the simulation model is verified by comparing the simulation speed with the experimental speed,and the simulation failure mode with the experimental failure mode,and according to the simulation process,the velocity change and failure mechanism of the two composite structures in the penetration process are analyzed,and the role of ceramic balls in the penetration resistance ability of the composite structures is discussed.