Study on dynamic mechanical properties of tungsten copper alloy and application of shaped charge

Abstract

The tungsten-copper alloy liner has better performance than the copper liner. In order to better study the jet forming and penetration characteristics and dynamic mechanical properties of tungsten-copper alloy-shaped charge liner, this paper uses a multi-functional mechanical experimental machine and a Hopkinson bar device to carry out quasi-static tensile and dynamic impact tests, respectively, and fit the Johnson-Cook constitutive equation. The obtained parameters are used to carry out numerical simulations and compared with the experiment. The results show that the stress of the dynamic impact curve is higher than that of the quasi-static stress, and the strain rate strengthening effect is more obvious. There is an adiabatic temperature rise at the strain rate and an obvious thermal softening effect at different strain rates. At the highest strain rate, it shows an obvious strain rate strengthening effect and obvious plasticizing effect, and the tungsten-copper alloy has a certain sensitivity to strain rate. The precision of the Johnson-Cook constitutive model is higher, and it can better describe the plastic flow stress of tungsten-copper alloy at a high strain rate. When the parameters of the fitted Johnson-Cook model are used in the numerical simulation, the error between the numerical simulation and the actual is small. The obtained Johnson-Cook model and dynamic mechanical properties can help the follow-up study on the influencing factors of tungsten-copper jet forming and fracture, including the effect of material strength on injection instability, the integration of the shear band model with hydrodynamics, and the comparison of injection molding penetration with copper liners provide relevant data.