A NEW METHOD TO IMPROVE THE FORMING PERFORMANCE OF EFP WITH FINS BY GROOVING ON THE LINER

Abstract

In order to solve the flight instability of Explosively Formed Projectile caused by irregular fins, different design schemes are carried out to test the forming performance of EFPs with fins. Grid target and laser high speed photography were used to capture the forming characteristics of EFP in experiment. Both liners with the structure of two combined arcs and the liner with the structure of combined arc and cone could form EFPs with fins. But the EFPs were with irregular fins and were accomplished with big angles of attack and a necking tendency. With a bigger tail, the liner with structure of two combined arcs is much better than the structure of combined arc and cone in the view of flight stability. Then a new method- grooving on the liner is put forward to obtain EFPs with regular fins. Typical grooving parameters such as grooving position and shape are chosen to obtain an optimal EFP with fins. It turns out that by grooving on the liner, it is feasible to acquire a rodshape EFP with regular fins which could meet the design requirements.