Experimental and theoretical research on influence of warhead's nose shape on penetrating steel plates
[Objective]This paper aims to explore the influence of a warhead's nose shape on penetrating homogeneous metallic plates.[Methods]A series of armor-piercing penetration tests are performed by launching sharp and blunt-nosed projectiles from a 92 mm smoothbore gun to impact Q345B and 921A steel target plates.By recording the initial and residual velocity measurements of the warhead before and after pen-etrating into the target plates using a target net and high-speed video camera,the failure modes and damage modes related to the plates and projectile after the penetration test are analyzed,and an improved estimation method is established for calculating the residual velocity of the penetration of armor-piercing projectiles with different nose shapes.[Results]The results indicate that the warhead's nose shape has a significant impact on both the damage mode of the pierced plate and the conversion between various types of steel plate for the purpose of obtaining equivalent ballistic performance.In terms of damage characteristics,the petal failure of the target plate is the dominant mode after penetration by a sharp-nosed projectile,while a blunt-nosed pro-jectile mainly contributes to the punching shear failure of the plate.In contrast with the K.A.Belkin formula for calculating the residual velocity of armor-piercing projectiles penetrating into plates,the proposed im-proved Thompson's formula in this paper is in better agreement with the test results.[Conclusion]The res-ults show that the proposed method is adaptable to the similar estimation of armor-piercing projectile perform-ance,thereby providing a basis for further research on the penetration of large-mass warheads into metallic plates.