Fragmentation is the process by which the casing of a projectile from a bomb, barrel bomb, land mine, IED, artillery, mortar, tank gun, or autocannon shell, rocket, missile, grenade, etc. is shattered by the detonation of the explosive filler.. The correct term for these pieces is "fragmentation" (sometimes shortened to frag) "shards" or "splinters" can be used for nonpreformed fragments.