The double explosive layer cylindrical compaction method

The standard cylindrical configuration for shock compaction is useful for the compaction of composite materials which have some plastic behavior. It can also be used to densify hard ceramics up to about 85% of the theoretical density (TMD), when low detonation velocity explosives (2-4 km s-1) are used. In order to attain higher densities, higher pressures will be needed. With the aid of computer simulations, it is shown that this can be realized without the risk of tensile rarefaction waves, by using two layers of explosives having different detonation velocities. This method has already resulted in a homogeneous B4C compact (87% TMD). After infiltration with Al, a B4C composite having a hardness ranging from 15 to 18 GPa could be obtained with this method. © 1999 Elsevier Science S.A. All rights reserved