长杆高速侵彻下装甲钢靶的等效强度

Equivalent Strength of Armour Steel against High-velocity Penetration of Long-rod Projectile

装甲钢是复合装甲的主要组分之一,针对其抗长杆弹高速侵彻等效强度不明的问题,建立了三维SPH-FEM耦合模型。在验证模型可靠性的基础上,开展钨合金长杆弹在1 000~1 800 m/s初速度范围内侵彻半无限300~600 HBW装甲钢的仿真研究,基于侵彻阻力和Walker-Anderson(W-A)模型对高应变率-绝热工况下靶钢的等效强度进行探索。研究结果表明:侵彻过程分为初始瞬态、准定常和剩余侵彻3个阶段,W-A模型在大部分工况下可准确计算侵彻深度和准定常段头尾速度;准定常阶段杆体直径与靶体等效强度近似保持恒定,侵彻阻力可由Poncelet公式描述。基于以上分析建立装甲钢等效强度-硬度非线性换算模型,结合W-A模型能准确预测长杆弹对半无限靶的侵彻深度。此模型表明等效强度与硬度正相关,但热软化的增强与应变率强化的减弱使等效强度的增速逐渐放缓。

Armour grade steel is one of the main components of composite armour.A 3D SPH-FEM coupling model is developed to investigate the equivalent strength of armour grade steel against the penetration of long-rod projectile.On the basis of verifying the reliability of the model,a simulation study on tungsten alloy long-rod projectiles penetrating a semi-infinite 300-600 HBW armour steel in the initial velocity range of 1 000-1 800 m/s is carried out.The equivalent strength of armour steel under high strain rate-adiabatic conditions is explored based on the resistance force and Walker-Anderson model.The calculated results show that the penetration process of tungsten long-rod projectiles into semi-infinite steel targets can be divided into three stages:initial transient,quasi-steady and residual penetration.In most conditions,Walker-Anderson model can be used to accurately calculate the depth of penetration and head velocity of quasi-steady stage.the diameter of rod body and the equivalent strength of target are approximately constant in the quasi-steady stage,thus the penetration resistance can be described by the Poncelet formula.According to the above analysis,a nonlinear conversion model for the equivalent strength and hardness of armour steel is developed.Combined with Walker-Anderson model,it can accurately predict the depth of penetration of long-rod projectiles against semi-infinite targets.The model shows that equivalent strength is positively related to hardness,but its increase slows down due to the enhancement of thermal softening and the weakening of strain rate hardening.