【摘要】 为了研究高应变率条件下高氮合金钢的剪切性能,用改装的Hopkinson压杆装置对高氮合金钢进行冲塞剪切测试.通过分析给出不同应变率条件下2种类型的高氮合金钢的剪切应力应变关系,从而研究材料的抗剪切强度和冲塞过程中局部剪切能量,并在位错动力学Seeger方程基础上提炼出高氮合金钢的动态剪切损伤本构关系,采用曲线拟合的方法拟合出不同材料参数.结果表明,改装的Hopkinson压杆装置能够有效地测试高氮合金钢高应变率剪切性能,2种类型的高氮合金钢的剪切强度均表现为正应变率效应,损伤积累阶段,材料耗能几乎呈线性增长,材料剪切损伤模型能够模拟高氮合金钢剪切性能的应变率效应.更多还原

【Abstract】 In order to obtain the dynamic shearing property of high N alloy steel,the plugging test was performed by using the improved Hopkinson pressure bar system.The dynamic shearing strengths and dynamic shearing deformed energies during plugging process were determined from the shearing stress-strain relationship at different super high strain rates.A dynamic shearing damage constitutive relationship was established based on the Seeger dislocation dynamics theory and the parameters in the equation were determined by using the curve fitting method.The results show that the dynamic shearing property of high N alloy steel could be obtained by the improved Hopkinson pressure bar system.These two type high N alloy steels have a kind of positive strain rate effect.The dissipation energy increases almost linearly with time at the damage accumulation stage,and the strain rate effect of dynamic shearing property could be described by dynamic shearing damage constitutive relationship.更多还原