Harvey armour

Harvey armor was a type of steel armor developed in the early 1890s in which the front surfaces of the plates were case hardened. The method for doing this was known as the Harvey process.

This type of armor was used in the construction of capital ships until superseded by Krupp armor in the late 1890s. It was invented by the American engineer Hayward Augustus Harvey.

The Harvey United Steel Company is a notorious cartel which existed only on paper and whose chairman was Albert Vickers. The year 1894 would see the ten main producers of armor plate, including Vickers, Armstrong, Krupp, Schneider, Carnegie and Bethlehem Steel, form the Harvey Syndicate.

Before the appearance of compound armor in the 1880s, armor plating was made from uniform homogenous iron or steel plates backed by several inches of teak to absorb the shock of projectile impact. Compound armor appeared in the mid-1880s and was made from two different types of steel, a very hard but brittle high-carbon steel front plate backed by a more elastic low-carbon wrought iron plate. The front plate was intended to break up an incoming shell, while the rear plate would catch any splinters and hold the armor together if the brittle front plate shattered.

Compound armor was made by pouring molten steel between a red-hot wrought iron backing plate and a hardened steel front plate to weld them together. This process produced a sharp transition between the properties of the two plates in a very small distance. As consequence, the two plates could separate when struck by a shell, and the rear plate was often not elastic enough to stop the splinters. With the discovery of nickel-steel alloys in 1889, compound armor was rendered obsolete.

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