Effect of air gaps on ballistic resistance of targets for conical impactors

High velocity penetration of a rigid conical impactor into a ductile target with air gaps between the plates is studied using the cylindrical cavity e xpansion approximation describing impactor-target interaction. It is showed that the latter model predicts improvement of the ballistic performance of the target with the increase of air gaps. It is found analytically that th e ballistic limit velocity of the target consisting of N plates with a fixe d total thickness with large air gaps increases with the increase of N. The conditions are discussed when the predicted effects can be most pronounced . (C) 1998 Elsevier Science Ltd. All rights reserved.