Types of Stainless Steel

Although there is some debate as to when stainless steel was invented, and by whom, there’s no doubt that the metal is one of the most useful and versatile products around today.

Stainless steel is usually divided into five types:

Also called the 300 series, this is by far the most commonly used steel, accounting for over 70% of all steel production. Its basic make up is 18% chromium and 8% nickel, boosted by additional elements such as manganese and nitrogen. It is highly resistant to corrosion and easily drawn into wires or hammered into thin sheets. Austenitic steel enjoys excellent hygiene properties, and it is commonly used in food processing equipment, kitchen sinks and chemical equipment.

This was actually the first steel to be commercially developed, and was originally mainly used to make cutlery. It has a higher carbon content than most other stainless steels, and also contains 18% chromium. Martensitic steels generally have low weldability and formability, and are somewhat less durable than austenitic steel. They are commonly used to make knife blades, surgical instruments, pins and shafts.

Together with Martensitic steel, this is known collectively as the 400 series. It can contain as much as 27% chromium, along with 10.5% carbon. Its high corrosion resistance makes it ideal for use in marine applications.

This is made from approximately half ferritic and half austenitic stainless steel, making it more corrosion resistant than any other type. It’s also easy to work with, and can easily be welded and formed into specific shapes.

Precipitation Hardening
The addition of aluminium, copper and niobium makes these steels extremely strong, meaning they can be machined into quite detailed and intricate shapes. Although tougher than austenitic steel, they are equally as resistant to corrosion, making them ideal for use in the manufacturing of aircraft parts, shafts and pumps.

Steelmor is one of the leading stockists and manufacturers of stainless steel products in South Africa. Contact us today to find out we can supply you with the highest quality products to meet your needs.