Experiments with Jacketed Rods of High Fineness Ratio

摘要

Cylinders of high fineness ratio can show severe integrity and stability problemsduring acceleration and free-flight phase. The paper describes a method to overcome these problems by adding an envelope to the slender cylinder thereby augmenting the stiffness under flexure. Theoretical considerations treat the pros and cons of jackets with different Young's moduli while looking at various parameters such as maximal deflection, total mass as well as muzzle and impact velocity. Special emphasis is given to the terminal ballistic efficiency which has been tested using jacketed model penetrators made of tungsten heavy metal with carbon-fiber reinforced plastic (CFRP) and steel envelopes. Some experiments were carried out with cannon-launched CFRP-jacketed tungsten rods of aspect ratios from 45 to 60 being accelerated up to 2000 m/s. In other penetration tests L/D=25 and 40 jacketed penetrators were shot onto homogeneous semi-infinite RHA targets and also spaced targets at 60 degrees incidence at velocities up to 2500 m/s by aid of a light-gas gun.