Stainless steel is an alloy

Stainless steel alloy elements

Which element brings which properties?

Stainless steel is not just made of one material, but is a perfect interplay of different elements. These different alloys give steel important properties such as corrosion resistance or make stainless steel rustproof. Here we show you which stainless steel alloy elements have which properties.

Alloy elements from A to Z

Get a quick overview with our graphic on the alloy elements.


  • aluminum: Aluminum ensures deoxidation in stainless steel and, together with nitrogen, becomes nitride. As an alloying element, aluminum reduces the magnetic properties of steel (coercive) and, if the alloy is high, strengthens the ferrite structure.
  • beryllium: This alloy element increases the structure of austenite, i.e. it separates austenite from the steel structure. At the same time, beryllium has a strong deoxidizing effect. On the other hand, the toughness is reduced in alloys with a higher beryllium content. Beryllium is used, for example, in spring steel.
  • boron: The alloy with boron makes stainless steel even stronger by absorbing the neutrons in the iron. The negative side effect is that stainless steel with boron is less resistant to corrosion.
  • Cerium: This element has a deoxidizing effect and reduces the risk of the stainless steel losing its oxide layer (resistance to scaling).
  • chrome: Chromium is one of the most important alloying elements for stainless steel. With the addition of chromium, the steel is less subject to wear, the tensile strength increases and the corrosion resistance is increased. Stainless steel (V2A or V4A) contains at least 12.2 percent chrome. The disadvantage is that stainless steel is more difficult to weld due to the chromium content. At the same time, thermal and electrical conductivity are reduced.
  • carbon: Carbon in stainless steel is important to harden the material and make it tensile strength. However, the carbon content must not be too high, otherwise the steel will become too brittle.
  • copper: If stainless steel contains copper, this improves the strength and weather resistance of the material. At the same time, there is less risk of the material breaking due to stretching.
  • manganese: If manganese is added to the stainless steel alloy, the material can be forged and welded more easily. In addition, the steel becomes stronger and less subject to wear.
  • molybdenum: This alloy element makes the stainless steel even harder and more tensile. At the same time, stainless steel with a higher molybdenum content is easier to weld. In return, this stainless steel becomes less ductile and malleable.
  • nickel: From a nickel content of eight percent, stainless steel becomes corrosion-resistant. So nickel is important for the steel to be rust free. Nickel is also required to increase the tensile strength and the so-called "yield point" of the stainless steel. In other words: the higher nickel content ensures that higher tension can act on the stainless steel without the material deforming.
  • phosphorus: Phosphorus makes stainless steel harder and increases its resistance to corrosion. However, the material can also become more brittle and thus break more easily under load.
  • sulfur: With the addition of sulfur, stainless steel can be drilled, milled or turned more easily (= increased machinability). For this, however, the ductility is reduced. This means that the steel is easier to deform.
  • silicon: With silicon, the scale resistance of stainless steel is improved. When casting steel, the melt becomes thinner with silicon. In addition, silicon strengthens the tensile strength and the yield point.
  • titanium: As an alloying element, titanium blocks so-called "intergranular corrosion". This means that titanium prevents the stainless steel from corroding from the inside at the boundaries of the individual elements under certain conditions and thus "crumbling".
  • Vanadium: The addition of vanadium makes stainless steel more tensile and at the same time easier to process. The steel can be protected from overheating with vanadium. In return, the wear resistance is reduced.
  • tungsten: The alloy element tungsten makes stainless steel more tensile.

Now at the latest it becomes clear what stainless steel is: A real “mixture” of elements, a material whose properties can be optimized depending on the alloy.

In your opinion, have we forgotten an important element? Then let us know!