An English metallurgist aims to improve the rifle

It was Sir Isaac Newton who, in a letter to his fellow scientist Robert Hooke, modestly stated, ‘If I have seen further it is by standing on the shoulders of giants.’ Pleasingly, even that expression itself was not Newton’s own – he was paraphrasing a saying coined by the 12th-century cleric Bernard of Chartres.

In the scientific world, there can have been very few discoveries that did not rely on the work of men and women who had gone before. In the case of metallurgist Harry Brearley, those shoulders belonged to scientists from France, Germany and his native England. However, in a twist on the usual story of one scientist painstakingly building on the work of others, Brearley found himself standing on those giants’ shoulders quite by accident. Furthermore – and most unusually for the metaphor – he wasn’t alone on the shoulders. In the years immediately prior to the outbreak of World War I there was a plethora of other metallurgists jostling for position with him. They came from Germany, the United States, Poland and (possibly) Sweden, and with one exception (the Swede, whose very existence is questionable), they were all endeavouring to invent the one thing that Harry Brearley came upon by accident. It’s true indeed that those whom the gods wish to destroy they first make mad.

Brearley was born in a small and cramped house in Sheffield, South Yorkshire in 1871, the eighth of nine children. He joined the city’s Brown Firth Laboratories, becoming its lead researcher in 1908. Four years later, the company was commissioned by a small arms manufacturer to find a solution to a common problem among gunmakers: the erosion of the metal in their weapons. Rifles are so called because of the spiral grooves or ‘rifling’ on the inside of their barrels. These spin the bullets as they leave the weapon, thus aiding their aerodynamic stability and accuracy. When they are worn away, the rifle loses its effectiveness. If Brearley could come up with a way of slowing down this process, rifles would have a longer life and their owners would be able to kill more sentient beings.

Brearley set to work in his attempts to produce a metal that would withstand the high-speed chafing it received every time a bullet sped along a barrel. It would not be easy. He experimented with metal alloys, adding varying amounts of chromium and carbon to iron to see what would happen. By August 1913, when fortune finally smiled on him, he had racked up a host of failures.

The romantics among us would like to believe that Brearley’s discovery – which, it must be said, did not actually help him with the problem he was working on – came about entirely as the myth portrays it. This avers that he was passing a pile of chunks of metal he had discarded as rejects when he happened to notice that one of his previous efforts stood out from the rest. Whilst the vast majority had rusted at the normal rate, this particular one sparkled up at him because it had barely rusted at all. He picked it up and in his hands he knew he had something special: the world’s first ever piece of stainless steel.

According to the British Stainless Steel Association, an organisation one would be foolish to gainsay on the topic of its favourite metal alloy, more credibility should be given to other, less thrilling accounts of the discovery. These versions claim:

It was necessary for Brearley to etch his steels with nitric acid and examine them under a microscope in order to analyse their potential resistance to chemical attack. Brearley found that his new steel resisted these chemical attacks and proceeded to test the sample with other agents, including lemon juice and vinegar. Brearley was astounded to find that his alloys were still highly resistant, and immediately recognised the potential for his steel within the cutlery industry.

The directors at Brown Firth Laboratories were less impressed, especially when the knife blades Brearley made out of his new wonder material simply rusted like any other steel. Thankfully, help was not far away. One of Brearley’s friends from his school days, Ernest Stuart, had turned out to be a particularly fine cutler and was a manager at R.F. Mosley’s Portland Works in Sheffield. In no time at all Stuart had honed the process by which Brearley’s new metal was hardened and ‘stainless steel’ came into being. (Brearley had actually coined the term ‘rustless steel’ but Stuart’s name for it was the one that prevailed.)

Steel is an alloy of iron and carbon and its discovery dates back to about 200 bc. Stainless steel, by contrast, is a metal that combines iron with at least 10.5 per cent chromium and a very small amount of carbon. This allows the chromium to form an oxidised coating over the surface of the metal, which is what keeps it both rust- and stain-free. Nowadays, silicon manganese is also added, while nickel, molybdenum and other elements may find themselves included in the mix as well.

It’s astonishing to consider the number of scientists who came so close to pulling off deliberately what Brearley did accidentally. Nearly a hundred years beforehand there were several metallurgists struggling with the problem of devising an iron that wouldn’t rust, but they either didn’t use enough chromium or added too much carbon or both. By 1875, a French scientist called Brustlein worked out that, to make a good stainless steel, it was imperative that the carbon content be kept to a minimal level. Two decades later, a German scientist called Hans Goldschmidt developed a process that made that possible. Frenchman Leon Guillet did actually invent a number of alloys which, today, would be considered stainless steel, but he somehow managed to overlook the fact that they were stainless and rustless. Just two years before Brearley’s happy accident, two Germans called Monnartz and Borchers noted that there were benefits to having a steel that included at least 10.5 per cent chromium in it. There were many other scientists besides these who had the holy grail of a rustless, stainless steel almost in their grasp and yet failed in their quest to attain it.

That hasn’t stopped a range of other people from asserting that they got there before Brearley. The most intriguing of these comes from the German Krupp Iron Works, which maintains that the iron-chrome-nickel hull it made for a yacht in 1908 was in reality the first stainless steel. Unfortunately, the claim cannot be verified because the vessel in question, The Half Moon, sank off the coast of Florida. Like a marine-disaster version of Schrödinger’s cat, until the yacht is located, its hull exists in two states: pristine and corroded.

The invention of stainless steel handed Sheffield many more decades of prosperity as it churned out countless items of cutlery. It saved the people of Britain from constantly having to polish their steel knives and forks to keep them from rusting. Where its use was adopted in lieu of silver by the upper echelons of society, it also saved their staff from the unending and onerous task of polishing the cutlery in order to maintain its lustre.

Although economic winds (presumably wafted by the vaunted ‘unseen hand of the market’) have blown out nearly all the furnaces that once gave Sheffield its nickname of the Steel City, there is still plenty of stainless steel being manufactured around the globe: over 40 million tonnes are produced per annum, a figure that has been rising steadily in recent years. The alloy is by no means limited to domestic use either. Stainless steel has been employed to create Newcastle’s iconic concert hall The Sage, as well as the Thames Barrier in London, and The Kelpies, a pair of 100-ft tall stainless steel-clad horse-heads – claimed to be the world’s largest equine sculptures – created by Andy Scott for the Scottish town of Falkirk.

Perhaps most fittingly, given the urban myth that surrounds its invention, stainless steel plays its own part in another urban myth. It’s a widely held belief that the shiny silver-coloured finial on the roof of the Chrysler Building in New York is made of hubcaps. That’s not the case – it’s just good old stainless steel.

As for a metal that was less susceptible to erosion when used in gun barrels – Brearley never did get around to discovering that.