Steel giving - charting 100 years of stainless steel
100 years after the invention of stainless steel, Emily Ranson delves into the history behind this everyday metal.
The name stainless steel refers to iron alloys containing at least 10.5% chromium, with other alloying elements, such as nickel and carbon, added to improve formability, weldability and strength. The term covers a wide range of types and grades, with the main requirement being that they are corrosion resistant for specific applications or environments.
Stainless steel: take five
• Ferritic – Type 400 series based on chromium, carbon is usually less than 0.1%. Ferritic is limited to use in relatively thin sections, due to its lack of toughness in welds. It is generally chosen for its resistance to stress corrosion cracking.
• Austenitic – Type 200–300 series derived from the addition of nickel, manganese and nitrogen, this is the most common stainless steel. Chosen for its combination of good weldability and formability, it is vulnerable to stress corrosion cracking.
• Martensitic – Type 400 series based on chromium with carbon levels of up to 1%. Martensitic is used where high strength and moderate corrosion resistance are required, but lacks the weldability and formability necessary for more delicate tasks.
• Duplex – Types such as 2205 (most widely used) and 2304 (a lean duplex) with a 50/50 microstructure of ferritic and austenitic. Duplex has high strength, resistance to stress corrosion cracking and moderate formability.
• Precipitation hardening – Part of the type 600 series, it has very high strength due to added elements including copper, niobium and aluminium. It can be machined into intricate shapes, and its corrosion resistance is similar to that of austenitic.
192 years in the making
1821-22 Pierre Berthier and Englishmen James Stoddard and Michael Faraday note that iron– chromium alloys are resistant to attack by certain acids.
1855 Sir Henry Bessemer takes out his first patent on a process for making cast iron more malleable by introducing air into the liquid metal, greatly reducing its carbon content.
1875 Henri Brustlein discovers that to create an alloy with a high percentage of chromium, the carbon content must remain below 0.15%.
1895 The aluminothermic reduction process for producing carbon-free chromium is developed by Hans Goldschmidt of Germany.
1904-6 French scientist Leon Guillet undertakes research on many ironchromium alloys, and later iron–nickel–chrome alloys, establishing the metallurgical characteristics of stainless steel. Despite failing to acknowledge the potential corrosion resistance of his materials, in 1905 he publishes a book called Stainless Steel.
1909 An in-depth work by W Giesen on chromium-nickel (austenitic 300 series) stainless steel is published in the UK.
1909 French national Albert Portevin studies what is now known as Type 430 ferritic stainless steel.
1911 Philip Monnartz, under his director W Borchers, in Germany, discover the importance of a minimum chromium content, with the corrosion resistance of steel increasing significantly if at least 10.5% chromium is present.
1913 On 13 August in Sheffield, UK, Harry Brearley creates a steel with 12.8% chromium and 0.24% carbon, which is considered to be the first ever stainless steel. He does so accidentally, having set out to create erosion-, not corrosion-resistant steel to prolong gun barrel life.
1915 During World War I, Brearley’s employer Thomas Firth & Sons has its entire production of stainless steel requisitioned to manufacture exhaust valves for aircraft engines.
1919 Sheffield cutlers begin regular production of stainless steel cutlery, surgical scalpels and tools.
1925 A stainless steel containing 18% chromium, 8% nickel and 0.2% carbon comes into use, known as 18/8 austenitic grade, the most widely used type today.
1928 The brewery industry installs the first stainless steel fermenting tank.
1929 The first stainless steel tanker is used to transport 3,000 gallons of milk.
1929 The top 88 metres of the Chrysler building in New York, USA, are clad in stainless steel.
1935 Heavy porcelain-enamelled cast iron sinks are replaced with ones made of 19/8 stainless steel in newly built homes.
1936 In Detroit, USA, six Deluxe Sedan stainless steel cars roll off the Ford production line, the first stainless steel cars ever made.
1953 Stainless steel breathing apparatus helps Edmund Hillary and Tenzing Norgay to reach the top of Mount Everest.
1954 The first stainless steel underwater TV camera is made.
1959 Calder Hall in Cumberland, UK, is the first nuclear power station built in England, relying on stainless steel for its high temperature resistance and safety factor.
1969 Stainless steel is used in all of NASA’s 13 Saturn V rockets for the Apollo space programme, which beats Neil Armstrong to landing on the moon.
1982-6 The stainless steel Thames Barrier in London, UK, becomes the longest movable flood barrier in the world.
1989 Opening of La Pyramide Du Louvre in Paris, France, with its stainless steel frame supporting 673 glass panels.
1996 Kuala Lumpur’s Petronas Twin Towers are covered in 65,000m2 of stainless steel.
2003 The Monument of Light in Dublin, Ireland, the tallest sculpture in the world at 120 metres high, is constructed of eight stainless steel hollow tubes.
2004 Chicago’s iconic Cloud Gate sculpture is constructed, using welded stainless steel plates.
2013 Stainless steel celebrates its centenary.