From Cutlery to Space Shuttles:
The History of Stainless Steel and Superalloys
We know a lot about stainless steel here at Ocean State Stainless, and not just the nuts and bolts of it, if you'll pardon the expression. Although not everyone shares our enthusiasm for the history of stainless steel, it is in fact a fascinating story that begins in the early 19th century and continues on today, fueled by a never-ending appetite for stronger high-performance materials for applications in the aerospace, medical, energy, and semiconductor industries.
Although Harry Brearley, chief of the research lab run jointly by John Brown & Co. and Thomas Firth & Sons in Great Britain, is generally credited with "inventing" stainless steel in 1913, research on the alloy had been going on in England, France and Germany for almost 100 years before the first patent was issued in 1919. In 1821 a Frenchman called Berthier discovered that when iron was alloyed with chromium it became resistant to some acids. Study and experimentation with this alloy continued over the next fifty years. Finally, in 1875, another Frenchman named Brustlein discovered that a very low level of carbon was important, however it was difficult to obtain. When low carbon ferrochrome became commercially available, improvements in stainless steel alloys really took off.
In 1912, Harry Brearley was looking for an erosion resistant gun barrel material when he began his work on what was a forerunner of today's 420. Those who worked under him went on to develop the common 18-8 (18% Chromium, 8% Nickel) stainless steels that a majority of fasteners are made out of today. The first commercial application of Brearley's work was table cutlery, made by Sheffields. It was not an overnight success. Brearley became known as the man who invented "the knife that would not cut".
Refinements were not far behind, however, and stainless steel (originally dubbed "rustless steel") became the miracle metal of the modern world. The beautiful, high gloss polish that can be achieved on stainless steel made it an attractive material for the Art Deco architectural style of the 1920's and 1930's, which was characterized by a streamlined, modern, almost futuristic look. Perhaps the most famous and beautiful example: the seven stainless steel clad arches at the top of the Chrysler Building in New York City, built in 1930.
So here was a metal that typified the new, modern world of the twentieth century. Its characteristics were corrosion resistance, low maintenance, and relative low cost. It was quickly put to work in many applications, both domestic and military -- everything from surgical scalpels to, quite literally, the kitchen sink. And of course, to assemble these devices made from the new miracle metal, you needed stainless steel fasteners.
But two uniquely twentieth century occurrences – the birth of the aerospace industry and World War II – quickly created an appetite for even stronger, more corrosion resistant materials that would function in high-temperature environments. Metallurgists began experimenting with "super alloys". Three classes of super alloys emerged: cobalt-base, nickel-base, and iron-base. One of the big breakthroughs came with the adaptation of a cobalt alloy, Haynes Stellite 31, for use in aircraft engines. There was also work on adapting Nichrome, a nickel-chromium alloy that had been developed in the first decade of the twentieth century for use as, of all things, toaster wire. This work led to today Inconel's, Monel's (Nickel Copper) and A286.
Although military and aerospace applications have often driven the search for newer, stronger, high-temperature materials, other industries have participated in, and benefitted from, the research. The medical industry, for example, needs special grades of stainless steel fasteners that can be in contact with bone and soft tissue for long periods of time. The semiconductor industry needs fasteners that are non-magnetic and have excellent chemical resistance.
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