From blister steel to crucible steel

The 'Steel City' Time Team Special saw Phil Harding and various experts attempting to recreate the production processes and steel-working techniques used in Sheffield in the past in order to make a knife. Their attempt – to produce 'blister steel' – was only partially successful, illustrating just how difficult and skilled a process this was.

Until the mid-18th century, the quality of steel was unreliable. Steel was made by heating iron bars, covered with charcoal, for up to a week. The end product was called 'blister steel'. Blister steel was then turned into 'shear steel' by wrapping blister steel bars into a bundle and re-reheating them before forging the bundle. The heat and action of the forge hammer welded the bundles together to the required size.

Although this steel was used to make razors, files, knives and swords, the process was extremely laborious and no more than 200 tons a year were produced in Sheffield in this way. Benjamin Huntsman's invention of the crucible steel process changed all of that. He was the first person to cast steel bars, producing tougher, high-quality steel in large quantities.

In 1846, the French metallurgist Monsieur le Play wrote of Huntsman: 'His memorable discovery advanced the steel manufactures of Sheffield to the first rank, and powerfully contributed to the establishment of the industrial and commercial supremacy of Great Britain.' Within 100 years, Sheffield was producing 20,000 tons of crucible steel per year a staggering 40% of total European steel production at this time.

At first, Sheffield cutlers refused to work with crucible steel because it was much harder than they were used to. French cutlers had no such reservations, providing a ready market for the new steel and producing higher-quality cutlery that began to challenge Sheffield's dominance. When the British government refused the Sheffield cutlers' demand that Huntsman's exports should be banned, the cutlers were forced to start using his steel for their own products.

Demand for the new crucible steel grew dramatically, and Huntsman moved to a vast new site at Attercliffe – an area that became the main location for specialist steel making in Sheffield.

With thanks to the Tilt Hammer website Time Works Project. For a description of the crucible steel process, see www.tilthammer.com/timeworks/crusteel.html

Channel 4 is not responsible for the content of third-party sites.

Text only

Back to Sheffield