Who invented stainless steel?
Rustproof steel, more than an invention, was a discovery, as it came about by chance, like many other human advancements. Since humans learned to create this material, its applications have continued to grow over the years. At CurioSfera-Historia.com, we explain the history of stainless steel and who its inventor was.
The inventor of stainless steel was the British metalworker Harry Brearley, born in Sheffield, Yorkshire, England, on August 8, 1913. He was born in 1871 in Sheffield, Yorkshire, where his father was employed as a furnace operator at the Firth Steelworks. He began working at the age of twelve as an assistant and later as an apprentice in the laboratories.
Studying at night school, he rose through the ranks and in 1907 was appointed director of the research laboratory shared by the Sheffield Firth and Brown Bayley steel companies. In 1912, he was investigating corrosion in rusted rifles. Studies on such properties had already been conducted. Alloys were mixtures of different metals, each of which provides a useful quality.
Stainless steel includes chromium in its alloy, but at least 12% of the steel must be chromium and up to 1% carbon for the stainless qualities to appear.
Frenchman Léon Guillet published a detailed study of such alloys in 1904, but did not point out the quality of corrosion resistance.
In 1909, Portevin also overlooked these qualities, while in an article by Giesen from 1909 the exact proportions used by Brearly in his patent already appear.
Germans Philipp Monnartz and Wilhelm Borchers discovered and explained the anti-corrosive properties. They obtained patent DE 246035 for an alloy containing 10% chromium and between 2% and 5% molybdenum.
Brearley produced his alloy in an electric furnace with 12.8% chromium. After heat treatment, the resulting metal resisted corrosion, but the government was not interested in using the material.
Brearley suggested to his company that they use it to manufacture stainless steel cutlery and asked a local craftsman to make some knives for him, since steel knives, which rusted when cleaned, were a problem. One of the directors of the cutlery department named it stainless steel after observing that vinegar did not leave stains on the material.
Firth did not want the patent and resisted Brearley's wishes, which explains the lack of a British patent. Brearley left the company and went to work as factory manager for rival Brown Bayley.
Meanwhile, Elwood Haynes of Indiana (United States) was researching the same field. His wife had asked him to manufacture cutlery that wouldn't rust. Independently, he discovered the chromium-steel alloy and filed a patent application before Brearley, but it was denied because "these chromium-steel alloys are not new." Finally, the patent for stainless steel was filed on September 5, 1916, and published as US 1197256.
Source: Curiosfera History
