Until Benjamin Huntsman invented the crucible process for casting steel around 1740, steel had been produced in only very small amounts. The Huntsman process liberated slag from "blister steel" through cementation and carburization. From this pure and uniform castings could be made.
Born in Barton-on-Humber, Lincolnshire, England, on 1704, Huntsman apprenticed as a clockmaker and locksmith in Epworth, Lincolnshire. In 1725 he startedhis own business in Doncaster. Striving to create better instruments, he searched for a higher quality steel and spent a number of years experimenting with different types of moldings. When he finally succeeded, he opened a steel plant in Sheffield (1740). His steel was considered too hard by the Sheffieldcutlers, and it was not accepted by them until after their counterparts in continental Europe had successfully used it.
The crucible is the vessel that holds molten steel or other metals while it is being melted or transferred. It is made of a highly heat-resistant materialsuch as clay or porcelain. Even today, some steel mills in Eastern Europe continue to transfer molten steel through ditches in an earthen floor.
Huntsman maintained secrecy over his foundry and his steelmaking process, never patenting it. In about 1750, his secret fell into the hands of Samuel Walker, a competitor. Walker made a great profit from Huntsman's process; yet Huntsman was able to produce a higher quality product and so was able to beat his competition and even expand his business in 1770. Judged by modern standards, the crucible process was very slow and extremely costly. However, it was the best steelmaking process at the time, and it remained so until it was replaced by the open hearth and electric furnace processes of the nineteenth century. Huntsman died in Sheffield, Yorkshire on June 21, 1776.