Research on the influence of cavity on compressive strength of electron beam controlled projectile

Fragments were premade on the cylindrical projectile using electron beam controlled technology, which induces cavities inside the material. Axial maximum compressive strength of the projectile is influenced by the structural parameters of cavity, including height, width, depth, slant angle, included angle, and circumferential quantity. Nonlinear dynamic software LS-DYNA was used to calculate the maximum compressive strength of each projectile with different cavity structure. Strength Influence Coefficient (SIC) was introduced to quantitatively characterize the influence of the cavity parameters on the axial maximum compressive strength of the projectile. The functions between the SIC and the cavity structure parameters were fitted, and an engineering predictive model was derived. Linear relationship was found between the maximum compressive strength and cavity height, width and circumferential quantity. The influence of cavity depth, slant angle and included angle on the maximum compressive strength was not obvious. The error between the calculation results of the predictive model and the experimental tests is 0.51%, which verifies the accuracy of the engineering predictive model.