There’s a difference between stainless
and stainless

What is stainless steel?

Stainless steel is a general term referring to a large number of qualities in which the most important alloying material is chromium. According to European Standard SS-EN 10088-1:2005, steel containing at least 10.5% chromium is defined as stainless steel. The European standard is also used as a Swedish standard. The carbon content must be restricted when corrosion resistance is important. Chromium is a primary alloying material. Chromium, which is not bound to carbon, determines corrosion resistance. In order to additionally improve resistance, other alloying materials, such as nickel and molybdenum, are also added.

The correct surface?

In order to achieve satisfactory corrosion resistance, the surface must be free of all oxides. Oxides form during heat working or heat treatment of the prod- uct. The oxide can be removed chemically through pickling, and/or mechanically, through grinding and polishing. The cleaner the surface is, the better the corrosion resistance will be.

The correct alloy?

The choice of a steel alloy depends on the properties the product is to have, and on what is most impor- tant for its function. The corrosion resistance in the environment where the final product is to be used
is naturally the most important property. However, other properties, such as mechanical strength and hardness, can also be important. Generally, a higher content of the alloying materials chromium, nickel and molybdenum provide better corrosion resistance.

Magnetism?

Certain types of stainless steel are magnetisable. What is most important is the microstructure of the steel and how they are tempered and heat-treated.

Literature references:

  • Swedish standard SS-EN 10088-1:2005
  • SMS Handbook nr 4, Rostfria stål (Stainless steel types), 6th edition, 2000
  • Karlebo handbook 15th edition, 2000

Several reasons to choose Marutex

  • Tested and type approved for corrosivity class C5
  • Heat-treated special steel for a long life span in harsh environments
  • Special stainless steel – high, consistent quality in material and performance
  • Optimal drilling capacity -drilling properties that shorten building times
  • Strength in a class for itself

Material composition in Marutex

Materialanalysis Marutex in %

Chromium 13,0 - 14,5
Molybdenum 1,8 - 2,2
Copper 0,4 - 0,6
Silicon 0,4 - 0,6
Manganese 0,4 - 0,6
Nickel 0,4 - 0,6
Carbon 0,20 - 0,30
Phosphorous 0,03 max
Sulphur 0,02 max