Oblique penetration effect of a tungsten ball on high hardness steel

In order to study the penetration performance and failure modes of high-hardness steel plates against tungsten balls with different angles, a ballistic gun was used to carry out $ \varnothing $8 mm, $ \varnothing $11 mm tungsten alloy spherical fragments at 0°, 20°, 40° angles to impact the thickness of 6 mm, 8 mm. In the hardness steel plate test, the limit penetration velocity (v₅₀) of the fragments impacting the steel plate was obtained; the relationships between the axial and radial deformation of the tungsten ball after the impact and the failure mode of the target plate and the impact velocity were analyzed. It is found that the failure mode of the high hardness steel plate is mainly the compression opening. For the pit failure and shear failure along the thickness direction, the shear fracture increases as the angle increases. The experiment was simulated by the method of finite element simulation. The simulation results were compared with the test results. The damage morphology of the target plate and the limit penetration velocity were in good agreement. The validity of the numerical simulation model and parameters was verified, and the numerical simulation method was used. The influence of the impact angle on the energy absorption mode of the target plate was studied, and the existing calculation formula of the limit penetration velocity was revised based on the experimental data. The results show that as the penetration angle increases, the limit penetration velocity increases, and the larger the penetration angle, the faster the limit penetration velocity increases; the revised limit penetration velocity calculation formula has a wider application range and higher accuracy, and has better engineering applications. As the angle increases, the energy absorption mode of the target plate gradually changes from compression opening to shearing plugging, and when the angle exceeds 50°, the energy consumption of shearing plugging will exceed the energy consumption of compression opening.