Early modern steel included Blister Steel manufactured by the cementation process which was first made around the 16th century in Italy and soon after in England were it was produced in Coalbrookdale by Basil Brooke around 1610.Â Wrought iron bars was the raw material used in the process, and was still used up till the 19th century.
Another early modern steel was Crucible Steel which was melted in a crucible rather then being forged.Â This resulted in a more uniform structure with better composition throughout.Â Earlier furnaces could not reach high enough temperatures to melt steel.Â Modern crucible steel resulted from the invention of Benjamin Huntsman in the 1740’s. Blister Steel (same as above) was melted in a crucible in side a furnace, & cast into ingots normally.
Early modern steel era ended and Modern steel making era began with the Bessemer Process named after it’s inventor Henry Bessemer who took out a patent on the process in 1855. although this process had already been used centuries before in china and other countries it was not used on an industrial scale before.Â The process was independently discovered in 1851 by William Kelly. The Bessemer process was the first inexpensive industrial process for mass production of steel from molten pig iron.Â The key to the process is the removal of impurities from the iron by oxidation by air being blown through the molten iron.
the Bessemer Process which revolutionized steel manufacture by cutting cost and increasing production speed and decreasing labor requirements.Â this brought the price of steel down to a similar priced wrought iron, which for the first time in history made steel an affordable material for building bridges or to be used in the frame work for buildings, most manufactures switched from wrought iron to steel after this.Â
below is a picture of a Bessemer converter