Corrosion handbook

24 06/21
MATERIAL NUMBER
Description
The system of numbering materials in accordance with EN 10088-1:2014 is used
in several countries. Each number has five digits, such as 1. 4404
The first digit 1 means steel, the second and third digits 44 mean chemically
resistant steels with Mo, and without Nb or Ti. In addition to designation 44, the
following designations for stainless steel exist:
“41” = with Mo, without Nb and Ti, Ni < 2,5 %
“43” = without Mo, Nb and Ti, Ni ≥ 2,5 %
“44” = with Mo, without Nb and Ti, Ni ≥ 2,5 %
“45” = with additional elements
The last two digits 04 designate the exact alloy.
AISI DESIGNATION (E.G. 316)
Description
The designation system of the American Iron and Steel Institute (AISI) is used
worldwide. It consists of a number to which one of several letters may be added
depending on the composition.
200 – designates an austenitic steel containing chromium, nickel and manganese
300 – designates an austenitic steel containing chromium, nickel
400 – designates ferritic and martensitic chromium steels
The additional letters (some shown below) indicate the following:
L = low carbon Ti = titanium
The newly-developed duplex stainless steel grades have a four-digit designation
(e.g. 2205 for the 1.4462)
SHORT NAME DESIGNATION
Description
X 2 Cr Ni Mo 17 12 2
X = High-alloy steel
2 = Carbon content in 1 / 100 %, in this case: C= 0.02 %
Cr = Chromium, in this case: 17 %
Ni = Nickel, in this case: 12 %
Mo = Molybdenum, 2 %
This steel grade in the given examples corresponds to the AISI type 316 L and the
DIN material no. 1.4404.