通过电子万能试验机和分离式霍普金森拉杆（SHTB）拉伸试验分别获得2024-T3铝合金材料准静态和高应变率两种应变率下的应力-应变曲线。铝合金材料的本构关系由能够反映材料硬化效应和应变率强化效应的John-son-Cook材料模型描述，方程中的4个参数通过不同应变率下的应力-应变曲线拟合得到。基于瞬态动力学软件PAM-CRASH，结合材料动态力学性能试验所获得的2024-T3铝合金Johnson-Cook模型方程，耦合光滑粒子流体动力学（SPH）方法和有限元（FE）方法建立2024-T3铝合金平板的鸟撞数值模型，数值计算所得动态响应与鸟撞试验结果吻合较好，表明建立的鸟撞数值计算模型是合理、可靠的，整个分析流程从材料动态力学性能试验、鸟撞数值计算到最终的鸟撞试验验证为飞机结构的抗鸟撞设计与分析提供了有力的参考。%Stress-strain curves at quasi-static and high strain rates of 2024 -T3 aluminum alloy were measured using dynamic tensile tests with an electronic universal testing machine and a split Hopkinson tensile bar (SHTB).The constitutive model of this aluminum alloy was described with Johnson-Cook model reflecting the material hardening effect the strain rate strengthening effect.4 parameters in Johnson-Cook equation were obtained by using stress-strain curves fitting at different strain rates.By combining the smooth particle hydrodynamics (SPH)method and the finite element (FE)method,and using Johnson-Cook equation of 2024-T3 aluminum alloy,the numerical model of bird impact on a 2024-T3 aluminum alloy square plate was established with the transient dynamic software PAM-CRASH.Dynamic responses of the plate with numerical calculation agreed well with the test results of bird impact.It was shown that the numerical calculation model is reasonable and reliable.The whole analysis process including material dynamic tests, numerical calculation and bird impact tests provided a reference for anti-bird impact design and analysis of aircraft structures.
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