Iron casting is comparatively brittle, it is not suitable for purposes where a sharp edge or flexibility is required. It is strong under compression, but not under tension. Cast Iron was first invented in
Ductile Iron Casting pots were made at many English blast furnaces at that period. In 1707, Abraham Darby patented a method of making pots (and kettles) thinner and hence cheaper than his rivals could. This meant that his Coalbrookdale Furnaces became dominant as suppliers of pots, an activity in which they were joined in the 1720s and 1730s by a small number of other coke-fired blast furnaces. The development of the steam engine by Thomas Newcomen provided a further market for cast iron, since this was considerably cheaper than the brass of which the engine cylinders were originally made. House radiator, Pneumatic valve A great exponent of cast iron was John Wilkinson, who amongst other things cast the cylinders for many of James Watt’s improved steam engines until the establishment of the Soho Foundry in 1795. The major use of cast iron for structural purposes began in the late 1770s when Abraham Darby III built the