Austenitic stainless steels represent steel alloys that contain an austenitic phase structure and are the most commonly used group of stainless steels.

Austenitic stainless steel grades have a face-centered cubic (FCC) crystal lattice structure, cannot be hardened by heat treatment, and are non-magnetic. However, academic studies have shown that at room temperature, the austenitic structure can spontaneously transform into a martensitic structure. These studies reveal that steel alloys with an austenitic phase can exhibit magnetism spontaneously.

Therefore, the common industrial belief and conclusion that “if it attracts a magnet, it is not stainless steel” is incorrect.

(Ref: Mészáros, István, and János Prohászka. “Magnetic investigation of the effect of α′-martensite on the properties of austenitic stainless steel.” Journal of Materials Processing Technology 161.1-2 (2005): 162-168.)

By examining cooling curves, it is a straightforward observation for almost any metallurgist or materials engineer that various phase transformations can occur. You can find all the details about Austenitic Stainless Steel Grades by searching on the Poyraz Stainless website.

Austenitic Stainless Steel Grades include: AISI 304 (1.4301), AISI 304L (1.4307), AISI 303 (1.4305), AISI 316 (1.4401), AISI 316L (1.4404), AISI 316Ti (1.4571), AISI 321 (1.4541), AISI 310 or 310S (1.4845), AISI 347 (1.4550), AISI 316LMo (1.4435), 316LVM (1.4441), 904L (1.4439).

Ferritic and super-ferritic stainless steel alloys are a class of alloys that contain 10.5% or more chromium and little to no nickel content. They are magnetic.

In Turkey and especially in Europe, the most commonly used ferritic stainless steel grade is AISI 430 (1.4016). In terms of corrosion resistance, ferritic stainless steels are weaker compared to other stainless steel classes.

However, their stable pricing has contributed significantly to the widespread use of ferritic stainless steels.

Grades of ferritic stainless steel available from our stock or on order include:
AISI 430F (1.4105), AISI 430 (1.4016), and AISI 446 (1.4762).

The class of stainless steel alloys that can be hardened through a mechanism called Precipitation Hardening is referred to as PH steels. These steels can undergo heat treatment, resulting in improved mechanical properties.

AISI 630 (also known as 1.4542 or 17-4 PH) is the most commonly used grade within this alloy class. As a result of the metallurgical process known as precipitation hardening, the material develops a magnetic phase structure.

Common PH stainless steel grades include:
17-4 PH (630 – 1.4542), 15-5 PH (1.4545 – 1.4548), and 13-8 Mo PH (1.4534).

Martensitic stainless steels have a phase structure ideal for applications requiring high and relatively good mechanical strength. They are magnetic.

Their mechanical strength can be improved and hardened through heat treatment.

The most common martensitic stainless steel grades are 410 and 420.

Technical details are available on the Poyraz Stainless website.

Martensitic Stainless Steel Grades:
AISI 420A, B, D (1.4021, 1.4028, 1.4034), AISI 440B, C (1.4112, 1.4125), AISI 416 (1.4005), AISI 410 (1.4006).