Building materials, group 2 steels.

metallurgy

26/12/2021


Group 2 steels are designated on the basis of their chemical composition and are divided into 4 subgroups.

Subgroup 2.1

Non-alloy steels (except free cutting steels) with a manganese content of less than 1%;
The designation includes successively :
The letter C
One hundred times the specified average % carbon content:
[C x 100 % carbon content].
Example: C35 = steel with 0.35% carbon.

Subgroup 2.2

Non-alloyed steels with manganese ≥ 1%, non-alloyed free-cutting steels and alloyed steels (except high-speed steels) with a content of each alloying element inferior of 5%.
The designation includes successively:
1) One hundred times the specified average % carbon content.
2) The chemical symbols of the alloying elements in descending order of the element contents.
3) Numbers representing the average content of each alloying element from its multiplier:

ABCDEF
1
Alloying elementsMultiplier coefficient
2
Cr, Co, Mn, Ni, Si, W4
3
Al, Be, Cu, Mo, Nb, Pb, Ta, Ti, V, Zr10
4
Ce, N, P, S100
5
B1000
6
Steel with 0.36% C
7
Example: 36 Ni Mo 16.1016/4 nickel
8
10/10 molybdenum

Subgroup 2.3

Alloy steels (except high speed steels) with a content of at least one alloying element ≥ 5%.
The designation consists successively of :
1) The letter X
2) One hundred times the specified average carbon content.
3) The chemical symbols of the alloying elements in descending order of the element contents.
4) The numbers representing the average content of each alloying element separated by a hyphen,
Example: X 5 CrNi18-10 which means: Steel with 0.05% C - 18% chromium (Cr) - 10% nickel (Ni)

Subgroup 2.4

High speed steel.
The designation includes successively :
1) The letters HS
2) The numbers separated by a hyphen, specifying the contents of the alloying elements in the following order:
Tungsten (W), Molybdenum (Mo), Vanadium (V), Cobalt (Co).
Example: HS2 9-1-8 HS6-5-3.