Stainless steel: Afbeelding 1 Stainless steel: Afbeelding 2

Often used stainless steel grades:

For vessels, Deprest uses frequently following stainless steel grades:

  • RVS304 = 1.4307
  • RVS316 = 1.4404
  • RVS316Ti = 1.4571
  • duplex and superduplex qualities e.g. 1.4462
  • special RVS types and nickel alloyed materials such as Hastelloy, Inconel, Incoloy, 1.4000, SMO and Uranus. Click here for a list of the special materials that we can process.

Generally, the client determines the quality of (stainless) steel that needs to be used

Stainless steel, some technical information

Stainless steels are iron alloys with at least 10.5% chromium added and up to 1.2% carbon. These values are, after all, the tipping point where steel begins to form a self-healing oxide layer (also known as oxide or passivation layer), so that the underlying metal is protected, and the corrosion resistance greatly improved. This oxide layer (the name speaks for itself) is spontaneously formed by contact with air (oxygen) and results in a layer that is passive and therefore more corrosion resistant. Technically the correct term is rust resistant, not rust free. If the steel surface is damaged through circumstances, then initially the iron alloy will be available again without oxide layer. At this moment the material is particularly vulnerable, but as a rule the oxide layer, once in contact with the air, restores itself spontaneously. Of course there are many different iron alloys that meet the definition of 'stainless steel', one even more corrosion resistant than the other. In addition to iron, chromium and carbon substances such as nickel, molybdenum, titanium, etc. are also added. The most used alloy, RVS304, consists of 18% chromium and 8% nickel.

Qualities and material numbers

It does not make things easier that different qualities, especially the stainless steel qualities, are indicated in different ways, either via the material number according to the EN number or according to AISI / ASTM, or even according to other standards or commercial names. The most convenient lookup tool is the one found on the Eurinox website (see link in appendix).