Types of Stainless Steel

Types of Stainless Steel and Their Uses



Stainless steel refers to a group of steel that is highly resistant to corrosion. Its corrosion resistance can be attributed to a chromium-rich oxide film that forms on its surface, which is also referred to as the "passive layer." It also contains varying amounts of carbon, silicon and manganese. Elements, such as nickel and molybdenum, may also be added to introduce other beneficial properties like enhanced formability and even more resistance to corrosion.

Stainless steel is used in everything from large architectural structures down to small chairs. For example, the famous Gateway Arch in St. Louis is 630 feet high and clad entirely with stainless steel.

While the anti-corrosive advantages of a iron-chromium alloy was known as far back as the early 19th century by French metallurgist Pierre Berthier, it wasn't until the early 20th century when it was produced with just the right properties Duplex Plate.

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Stainless steel is generally divided into five types:

1. Ferritic

The simplest composition contains iron and chromium, which is referred to as the ferritic stainless steels, since their crystal structure is called ferrite. These are magnetic, and are used in products such as automobile trim and dishwashers. They are generally the cheapest form, but come with downsides as well, such as difficulties welding and forming. Examples of ferritic steel use is in mufflers and home heating systems.

2. Austenitic

The most common stainless steel group, austenitic's microstructure is derived from the addition of nickel, manganese and nitrogen. Unlike ferritic, its structure is ideal for welding and forming. Some examples where austenitic steel can be used are in cookware and washing machine baskets Super Duplex Plate.

3. Martensitic


Martensitic steels are similar to ferritic, since they are based on chromium. However, they have higher carbon levels (as much as one percent). This allows them to be hardened and tempered. Martensitic is more commonly found in long products than in sheet and plate form, and they have generally low weldability and formability. Examples of martensitic steel use are cutlery and valve parts.

4. Duplex

The structure of duplex steels is about 50 percent ferritic and 50 percent austenitic, which gives them a higher strength than either of those steels. They are resistant to stress corrosion cracking and are weldable and are magnetic. Duplex may be used in pipes and architectural structures Duplex Plate Suppliers

5. Precipitation Hardening

These steels can be very strong by adding elements like copper, niobium and aluminum to the mix. During a very high heat treatment, very fine particles form in the steel which give it its strength. Precipitation hardening steels can be machined to very intricate shapes. The corrosion resistance is comparable to standard austenitic steels, but better than that of straight chromium ferritics. One possible use for this kind of stainless steel is aerospace components.