HISTORY OF STAINLESS STEELS
In the natural course of life, stainless steel finds its application in every field, ranging from simple design materials to more complex designs. Considered one of the most important classes of alloys, stainless steel was developed in the early twentieth century in Great Britain and Germany. Although there are corrosion-resistant non-ferrous metals such as nickel, nickel silver (nickel-copper-titanium alloys that do not contain silver but are similar), copper, brass, and bronze, these materials are more expensive and less durable than stainless steels.
Although steels containing chromium (Cr) were used towards the late 1800s, it was not known that chromium forms a corrosion-resistant oxide layer on the surface. In 1913, while developing rifle barrel steels, Harry Brearley discovered martensitic stainless steels. He then observed that a steel containing 0.3% carbon and 13% chromium was highly resistant to wear and very difficult to rust. In 1915, it was reported in a New York Times publication that Brearley had discovered stainless steel. Grade 420 stainless steel forms the foundation of the cutlery manufacturing industry and is still used in today’s industry.
Around the same period, steels used in Germany containing high amounts of nickel were resistant to dulling but not to corrosion. In 1912, Benno Strauss and Eduard Maurer discovered chromium-nickel based austenitic stainless steel, and austenitic stainless steels quickly replaced martensitic and ferritic stainless steels. This steel grade was soon used for the production of nitric acid storage tanks in the chemical industry. During the 1920s and 1930s, rapid developments were observed in commonly used stainless steel grades still popular today, such as 302 (18% Cr, 8% Ni), 316 (1.4404 or 18% Cr, 8% Ni, 2.5% Mo), 410 (12% Cr), and 430 (17% Cr). In the 1950s, stainless steels were considered precious metals. The global nickel crisis and price increases in the 1970s led to new developments in stainless steel production. Studies conducted during this period discovered that nitrogen (N) is an important austenite former, and even in small amounts, it reduced the need for nickel usage.