What makes a steel component “stainless”? Most people recognize stainless steel is an alloy that does not rust. But why doesn’t it rust? Steel that is made with at least 10.5% chromium is considered “stainless” and the chromium is what makes the metal anti-corrosive. There are actually four distinct types of stainless steel.
• Austenitic – This is the most commonly used stainless steel and is derived from nickel and manganese. This type is easy to weld and is non-magnetic. Household appliances, containers, and basic industrial piping are typically made from this type of steel.
• Ferritic – This steel has better corrosive resistance properties because of higher levels of chromium. Ferritic steel is ideal for boiler, washing machines, or mufflers.
• Duplex – Stainless steel like Duplex is a combination of austenitic and ferritic. This steel is widely used by stainless steel tank manufacturers because of the high strength of the metal.
• Martensitic – This type is most often used in applications such as knives or turbine blades. Martensitic is moderately resistant against corrosion but it is very strong which makes it ideal for cutting.
Most historians would agree that Leon Guillet, Elwood Haynes and Harry Brearley were all pioneers of discovering stainless steel. In 1912 Brearley was working for a research laboratory in England to discover solutions to stop gun barrels from rusting. While working on this project he discovered the stainless steel alloy. He applied for US patents but only to discover that Elwood Haynes had already filed for the patent. The duo then worked together to form the American Stainless Steel Corporation. Haynes was also the owner of Haynes Automobile Company in which he incorporated the stainless steel innovations into the mass production of his cars.