How many types of stainless steel are there?

In previous posts, we have talked about the main properties of stainless steel: its high durability, its hardness, its toughness… But to know exactly what kind of steel is better for a product or application, we must know what kinds of steel exist.

Stainless steel, an alloy, is as popular as it is strong, and is becoming increasingly popular thanks to its versatility. It can be adapted perfectly to a wide range of products, from industrial parts to jewelry to mobile phones to cutlery.

Types of stainless steel

Stainless steel is classified into four families or categories depending on its crystalline structure, although there is a fifth that could be included in the previous ones, called “precipitation hardening”.

This classification is governed by the elements in the steel and the relative quantity of each material involved.

– Austenitic stainless steels

Austentic stainless steels are some of the most popular and high-performing ones. These steels are chrome-nickel alloys with a fairly low carbon content. They are some of the most widely used stainless steels due to their excellent formability, very good weldability and also great resistance to different types of corrosion. In addition to these characteristics, they are also known to withstand extreme temperatures and lend themselves very well to cleaning and sanitization.

A few more features:

  • They are not magnetic.
  • They are cold hardened.

The vast majority of stainless steel produced today is made of austenitic steel, and it is very common to use it in kitchen equipment and material due to its sanitizability. It is also used in the pharmaceutical, chemical and textile industry.

– Ferritic stainless steels

Ferritic stainless steel is an alloy created mainly with chrome, which makes this material more economical than others. And although it has a lower price, this does not mean it has any lack of strength or durability. It has a high resistance to corrosion and can be used for long periods in difficult environments, and even undersea.

A few more features:

  • It is magnetic.
  • It is cold hardened, due to its slight hardness.

Martensitic stainless steels

Martenistic stainless steels were some of the first stainless steels marketed and although they are somewhat less durable than austenitic or ferritic steels, they are still widely used. This is an alloy created mostly with chrome and carbon, although it also does contain some nickel and molybdenum.

Heat treatment gives them great hardness and strength and they have an acceptable level of corrosion, so they are generally used in cutlery, silverware or medical/surgical instruments.

A few more features:

  • They are magnetic.
  • They are hardened by heat treatment.

– Duplex stainless steels

Duplex stainless steels are a mixture of austentic and ferritic steels. In raw material terms, they have a high chrome and low nickel content. Thanks to this combined alloy, the resistance is much better against corrosion cracking, and it is one of the most highly appreciated due to its strength and durability.

A few more features:

  • They are magnetic.
  • Good weldability
  • They cannot be hardened by heat treatment.

– Precipitation-hardening stainless steels

In many classifications, these are not included as such, but it is important to differentiate this family from the previous ones. They are an alternative, combining the properties of martensitic and austenitic stainless steels.

From martensitic steels they get their high strength, and from austenitic ones their great resistance to corrosion.

ULMA Forged Solutions’ high-quality materials

ULMA Forged Solutions makes the quality of its forged products its main concern.

Our clients know that they can trust ULMA when they need forged parts, as well as other types of parts made of superior materials and at competitive prices. ULMA Forged Solutions manufactures products from the following materials, among others:

  • Carbon steel / LTCS / HYCS
  • Alloy steel
  • Stainless steels
  • Duplex
  • Super duplex alloys
  • Nickel alloys
  • Monel alloys
  • Copper
  • Aluminium
  • Titanium

We produce our forgings from a wide variety of materials to meet the different needs of our customers in many different industries and areas of activity.