HEAT nổ rồi mới xuyên nhá, có điều xuyên bằng dòng kim loại nóng chảy nên sau khi xuyên sẽ gây cháy nổ
@panzerkelin :Second World War
British naval 15-inch capped armor-piercing shell, 1943During WWII, projectiles used highly alloyed steels containing nickel-chromium-molybdenum, although in Germany, this had to be changed to a silicon-manganese-chromium-based alloy when those grades became scarce. The latter alloy, although able to be hardened to the same level, was more brittle and had a tendency to shatter on striking highly sloped armor. The shattered shot lowered penetration, or resulted in total penetration failure; for armor-piercing high-explosive (APHE) projectiles, this could result in premature detonation of the HE filling. Highly advanced and precise methods of differentially hardening the projectile were developed during this period, especially by the German armament industry. The resulting projectiles gradually change from high hardness (low toughness) at the head to high toughness (low hardness) at the rear and were much less likely to fail on impact.
APHE shells for tank guns, although used by most forces of this period, were not used by the British
http://en.wikipedia.org/wiki/Armor-piercing_shot_and_shell