Naval Armour

A Brief History of Naval Armour - Successfully Forging Onwards > .  

Battleship Bulges - WW1 - WW2 SiHi > .

Brittle/ductile transition > .
Puddling furnace > .
Armour manufacture post-WW1 > .

Advances in metallurgy - Harvey, Krupp
https://en.wikipedia.org/wiki/Harvey_armor .
https://en.wikipedia.org/wiki/Krupp_armour .
https://en.wikipedia.org/wiki/Rolled_homogeneous_armour .
https://en.wikipedia.org/wiki/Vehicle_armour .

Composite armour is a type of vehicle armour consisting of layers of different material such as metals, plastics, ceramics or air. Most composite armours are lighter than their all-metal equivalent, but instead occupy a larger volume for the same resistance to penetration. It is possible to design composite armour stronger, lighter and less voluminous than traditional armour, but the cost is often prohibitively high, restricting its use to especially vulnerable parts of a vehicle. Its primary purpose is to help defeat high explosive anti-tank (HEAT) projectiles.

HEAT had posed a serious threat to armoured vehicles since its introduction in World War II. Lightweight and small, HEAT projectiles could nevertheless penetrate hundreds of millimetres of the hardest steel armours. The capability of most materials for defeating HEAT follows the "density law", which states that the penetration of shaped charge jets is proportional to the square root of the shaped charge liner density (typically copper) divided by the square root of the target density. On a weight basis, lighter targets are more advantageous than heavier targets, but using large quantities of lightweight materials has obvious disadvantages in terms of mechanical layout. Certain materials have an optimal compromise in terms of density that makes them particularly useful in this role.
https://en.wikipedia.org/wiki/Composite_armour .

Chobham armour is the informal name of a composite armour developed in the 1960s at the British tank research centre on Chobham Common, Surrey. The name has since become the common generic term for composite ceramic vehicle armour. Other names informally given to Chobham Armour include "Burlington" and "Dorchester." "Special armour" is a broader informal term referring to any armour arrangement comprising "sandwich" reactive plates, including Chobham Armour.https://en.wikipedia.org/wiki/Chobham_armour .

https://en.wikipedia.org/wiki/Ironclad_warship .

Torpedo Defense Systems ..