Theoretical analysis on transition from interface defeat to penetration in the impact of conical-nosed long rods onto ceramic targets

Based on related investigations, theoretical analysis on the transition from interface defeat to penetration in the impact of conical-nosed long rods onto ceramic targets is conducted systematically in the present manuscript, and comparison with the case of the flat-nosed long rod is carried out. Considering that the radius of rod-target contact face is variable during the dwell process of the conical nose, an effective impact pressure on the target surface is introduced to represent its total effect, and the corresponding formulae of the critical impact velocity range are deduced out. Furthermore, the influences of the half apex angle and the initial radius of nose tip on the lower and upper bounds of critical impact velocity range are discussed in detail, and the decay of critical impact velocity derived from the conical nose is predicted reasonably. Besides, by considering the damage and failure characteristics within the ceramic target, the critical transition time from interface defeat to penetration is analyzed, and the corresponding analytical formula is provided. Related analysis is of great significance for the design of nose shape of long rods which are directed against ceramic targets.