An Accidental Discovery to Most Popular Material

Stainless steel is a remarkable material that has evolved enormously over the years since it was first discovered. Through its development, it rapidly became one of the most versatile and widely used alloys across various industries, but its creation and evolution isn’t widely known.

This article will discuss when the material was first used as well as some of the scientific and engineering innovations that it went through over the years.

English metallurgist Harry Brearly was the first to establish stainless steel in the 20th century; a major breakthrough. In 1913, he was working with steel alloys containing a high chromium content in Sheffield, England. People knew back then that certain elements could be added to steel to improve its properties but the exact process was not fully understood.

Brearley and his colleagues were melting various alloys in a crucible before shaping various test pieces which they submitted to heat treatments and corrosion assessments. Through a number of observations and experiments, he accidentally discovered a material that resisted corrosion much better than the traditional carbon steel; stainless steel.

This early stainless steel contained approximately 12-14% chromium and its resistance to corrosion was attributed to the formation of a thin, protective oxide layer on the surface of the metal. This layer was primarily composed of chromium oxide and ultimately prevented rusting, which contributes to stainless steel’s longevity.

Commercialisation of stainless steel

Other researchers had been working on the same experiments too, so it wasn’t long after 1913, that Brearly’s company began to commercialise the alloy. Initially they focused on cutlery and knife blades but they could never have imagined what the material would become.

Over the prevailing years, advancements in alloy composition, processing techniques and scientific understanding have led to the development of many stainless steel grades tailored for specific applications. This includes 304 grade stainless steel, 430 grade stainless steel, duplex stainless steel and many others.

Major stainless steel developments

Over the years, several key developments occurred in relation to the alloy.

In the 1920s, German metallurgist Eduard Maurer further improved corrosion resistance and made stainless steel suitable for a wider range of applications. The first and second world wars accelerated further development too as it was used in aircraft, weaponry and naval equipment where corrosion resistance was critical.

304 grade or food grade stainless steel was also developing around this time. It was an early discovery but it has advanced immeasurably since to become one of the most popular grades. Today, 304 grade is also known as 18-8 stainless steel as it contains 18% chromium and 8% nickel. It has excellent corrosion resistance and is often used in food processing equipment.

Duplex and ferritic alloys were developed in the mid 20th century; these offered improved strength and resistance to chloride stress corrosion cracking which made them optimal for marine and chemical processing applications.

Precipitation-hardening stainless steel alloys were developed between the 1940s and 1950s. They could be heat treated to achieve greater strength and hardness while retaining their corrosion resistance; this made them ideal for aerospace and nuclear applications.

Research and development efforts continue in the modern era and thanks to scientific advancements, we now have the highly specialised alloys including superaustentic and superduplex stainless steels.

We also see these alloys being used to create smaller products and system parts such as stainless steel pipe bends and valves in pipework systems.

The application of stainless steel today

The continuous development of stainless steel alloys has led to their widespread use in more industries than ever before. Some of the most common include the construction, plumbing and architectural industries due to the aesthetic appeal and durability of the material.

The automotive industry is also a large consumer of stainless steel for both stylistic and practical reasons. Within the chemical processing industry, stainless steel is a favourite. This is because it is resistant to all corrosive chemicals, making it ideal for storage tanks, pipelines and reactors.

Of course the aerospace and aviation industry are in the same line and use large amounts of stainless steel, particularly for aircraft parts.

As mentioned, the ability of stainless steel to withstand extremely high temperatures and corrosive environments makes it the ideal choice for the energy industry. It’s widely used in solar, wind and wave energy applications.

However, the food and pharmaceutical industries are two we may forget about when it comes to the use of stainless steel. But, its hygienic properties are invaluable here. Stainless steel pipework and pipe bends, tanks, storage systems and fittings contribute massively to ensuring end to end product purity.

In conclusion, stainless steel’s journey from a serendipitous discovery to a ubiquitous and versatile material that is used in practically every industry represents a remarkable man-made journey in science and engineering.

Continued developments have made it the material of choice and as research continues, there’s no doubt that it will adapt further to meet new challenges.

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