PENETRATION ANALYSIS OF HIGH-SPEED LONG ROD PROJECTILE INTO THICK METAL TARGET WITH FINITE DIAMETER

Based on the expansion theory of finite cylindrical cavity based on unified strength theory, combined with Tate abrasion rod model, and considered the influence of intermediate principal stress, free boundary on the side of target and the deformation and erosion of high speed (1500 m/s~2200 m/s) penetrating projectile, the radial stress of cavity wall of linearly hardened finite diameter metal target during high speed penetration is deduced, and the calculation model of penetration resistance and penetration depth is established, which is solved by MATLAB software. The analysis also includs a series of influencing factors of ballistic end-point effect, such as the difference of strength criterion. The analysis result shows that the proposed computing method can precisely describe the penetration dynamic responses. Through this method, a series of different criteria-based analytical solutions are obtained, and penetration depth ranges of targets with different ratios of target radius to projectile radius are predicted effectively. Moreover, it is perceived that a group of parameters, such as the strength parameter, the striking velocity, and the target radius; these parameters present an obvious influence on the anti-penetration performance of the target, among which the penetration resistance has decreased by 33.33%, and the penetration depth has increased by 15.93% as the strength parameter value changes from 1 to 0. In addition, the results have changed significantly when the ratio of target radius to projectile radius is less than or equal to 20, and the penetration resistance has decreased by 41.30% and the penetration depth has increased by 32.61% as this ratio changes from 19.88 to 4.9. It is indicated that the penetration performance is obviously affected by the target boundary size at this time, and it cannot be calculated as an unlimited-size target any more.