text: In anti-tank warfare, spalling through mechanical stress is an intended effect of high-explosive squash head (HESH) anti-tank shells and many other munitions, which may not be powerful enough to pierce the armour of a target. The relatively soft warhead, containing or made of plastic explosive, flattens against the armour plating on tanks and other armoured fighting vehicles (AFVs) and explodes, creating a shock wave that travels through the armour as a compression wave and is reflected at the free surface as a tensile wave breaking (tensile stress/strain fracture) the metal on the inside. The resulting spall is dangerous to crew and equipment, and may result in a partial or complete disablement of a vehicle and/or its crew. Many AFVs are equipped with spall liners inside their armour for protection.
  A kinetic energy penetrator, if it can defeat the armour, generally causes spalling within the target as well, which helps to destroy or disable the vehicle and its crew.
  An early example of anti-tank weapon intentionally designed to cause spallation instead of penetration is the wz. 35 anti-tank rifle.