Grouping system for steels

Group system for steel  

Group 1:

              Steels with a specified minimum yield strength ReH ≤ 461 N/mm²  a and with analysis in %: C ≤   0.24, Si ≤ 0.60, Mn ≤1.70, Mo ≤ 0.70b, S ≤ 0.045, Cu ≤ 0.40b, Ni ≤ 0.5b, Cr ≤ 0.3 (0.4 for castings) b, Nb ≤ 0.05, V ≤ 0.12b, Ti ≤ 0.05.

Sub-Group:

              1.1 to 1.4 ,

               

Group 2:

Thermomechanically treated fine grain steels and cast steels with a specified minimum yield strength ReH˃361 N/mm²

Sub-Group:

             2.1, 2.2,

              

Group 3:

Quenched and tempered steels and precipitation hardened steels except for stainless steels with a   specified minimum yield strength ReH ˃ 362 N/mm²

Sup-Group:

               3.1 to 3.3,

Group 4:

                Low vanadium alloyed Cr-Mo-(Ni) steels with Mo ≤ 0.7%, and V ≤ 0.11%,

Sub-Group:

             4.1 to 4.2,

Group 5:

                Cr-Mo steels free of vanadium with C ≤ 0.34% c

Sub-Group:

               5.1 to 5.4,

Group 6:

High vanadium alloyed Cr-Mo-Ni steels

Sub-Group:

               6.1 to 6.4,

Group 7:

Ferritic, martensitic or precipitation hardened stainless steels with C ≤ 0.35 % and 10.5% ≤ Cr ≤ 31 %

Sub-Group:

              7.1, 7.2, 7.3,

Group 8:

Austenitic steels

Sub-Group:

                8.1, 8.2, 8.3,

Group 9:

Nickel alloyed steels with Ni ≤ 9 %,

Sub-group:

                9.1, 9.2, 9.3,

Group 10:

Austenitic ferritic stainless steel (duplex)

Sub-group :

                10.1, 10.2,
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