EN 10083-1:1991 2C50 Steel: Specifications & Listings
EN 10083-1:1991 2C50: A higher carbon special steel for quenching and tempering to EN 10083-1:1991 (printed 2 C 50), with sulphur max. 0.035%. Supplied as semi-finished products, bars, rod, wide flats, hot rolled strip, sheet and plate, and forgings. Quenched and tempered tensile strength 750 to 900 MPa for ruling sections up to 16 mm.
Matched by chemical composition and mechanical properties, not a formal equivalence claim. Always verify against the applicable standard before substitution.
Chemical Composition (%)
C
Cr
Cr+Mo+Ni
Mn
Mo
Ni
P
S
Si
0.47-0.55
<=0.40
<=0.63
0.60-0.90
<=0.10
<=0.40
<=0.035
<=0.035
<=0.40
Mechanical Properties
Condition
Quenched and tempered, ruling section d <= 16 mm
Elongation
13% min
Hardness
Soft annealed: 217 HB max
Tensile Strength
750 to 900 MPa
Yield Strength
520 MPa min
More data from EN 10083-1:1991
From the standard
Other composition limitsTable III and its notes
Designation as printed
2 C 50
Pair grade
3C50 has the same limits except sulphur, controlled 0.020 to 0.040
Availability
Printed in brackets: introduced partly for the first time in this standard and not available from stock in all countries (Table III, note 6)
Improved machinability
Steels with lead or higher sulphur, up to about 0.100% S, may be supplied on request (Table III, note 3)
Restricted options
Without hardenability or quenched and tempered or normalized property requirements, a carbon range of 0.05 and/or Cr + Mo + Ni below 0.45 may be agreed (Table III, note 5)
Elements not quoted in Table III are not intentionally added without the purchaser's agreement, other than for finishing the heat. With hardenability requirements, slight deviations within Table IV are permitted except for carbon, phosphorus and sulphur.
Source: EN 10083-1:1991 (UNI EN 10083-1), Table III and its notes
Mechanical properties, quenched and tempered3 sections
Ruling section
Yield strength Re, min (MPa)
Tensile strength Rm (MPa)
Elongation A, min (%)
Reduction of area Z, min (%)
Impact KV, min (J)
d <= 16 mm, t <= 8 mm
520
750 to 900
13
30
-
16 mm < d <= 40 mm, 8 mm < t <= 20 mm
460
700 to 850
15
35
-
40 mm < d <= 100 mm, 20 mm < t <= 60 mm
400
650 to 800
16
40
-
Re is the upper yield strength or, if no yield phenomenon occurs, the 0.2% proof strength; A on gauge length 5.65 times the root of the original cross section; KV on longitudinal ISO V-notch test pieces, average of 3 values, no single value below 70% of the minimum. Ruling sections as in Appendix B. Sizes not listed are not covered by the standard.
Source: EN 10083-1:1991 (UNI EN 10083-1), Table IX
Mechanical properties, normalized3 sizes
Size
Yield strength Re, min (MPa)
Tensile strength Rm, min (MPa)
Elongation A, min (%)
d <= 16 mm, t <= 16 mm
355
650
12
16 mm < d <= 100 mm, 16 mm < t <= 100 mm
320
610
14
100 mm < d <= 250 mm, 100 mm < t <= 250 mm
290
590
14
Values also apply to the grades with hardenability requirements (H, HH, HL). Sizes not listed are not covered by the standard.
Source: EN 10083-1:1991 (UNI EN 10083-1), Table X
Maximum hardness by delivery conditionTable VIII
Treated to improve shearability (TS), max
255 HB
Soft annealed (TA), max
217 HB
Values also apply to the grades with hardenability requirements (H, HH, HL); not applicable to continuously cast slabs not further deformed.
Source: EN 10083-1:1991 (UNI EN 10083-1), Table VIII
Hardenability, end quench test (H)Hardness band
Hardness band (HRC, minimum to maximum) by distance from the quenched end (mm)
1
2
3
4
5
6
7
8
9
10
11
13
15
20
25
30
Distance from quenched end (mm)
1
2
3
4
5
6
7
8
9
10
11
13
15
20
25
30
Maximum, HRC
63
62
61
60
58
55
50
43
36
35
34
33
32
31
29
28
Minimum, HRC
56
53
44
34
31
30
30
29
28
27
26
25
24
23
20
Applies when ordered as 2C50 H. Provisional values for non alloy steels; a manufacturer whose band falls outside these limits informs the purchaser at ordering (Table V, note 1). End quench test at 850 ± 5 deg C (Table XIII).
Source: EN 10083-1:1991 (UNI EN 10083-1), Table V
Restricted hardenability (HH, HL), provisionalTable VI
Symbol
1 mm (HRC)
5 mm (HRC)
HH5
-
40 to 58
HH15
58 to 63
40 to 58
HL5
-
31 to 49
HL15
56 to 61
31 to 49
Apply to both the 2C and 3C grade. The figure after the symbol gives the distances (mm) at which the limits apply.
Source: EN 10083-1:1991 (UNI EN 10083-1), Table VI
Minimum hardness of strip as quenchedTable XI
Hardness, min
600 HV
Maximum strip thickness
2 mm
Applies to the quenching temperatures of Table XIII with oil cooling.
Source: EN 10083-1:1991 (UNI EN 10083-1), Table XI
Heat treatmentTable XIII
Quenching
810 to 850 deg C
Quenching agent
Oil or water
Tempering
550 to 660 deg C
End quench test
850 ± 5 deg C
Normalizing
830 to 870 deg C
Guidance values except the end quench test temperature, which is binding. Lower quenching temperatures generally for water, upper for oil; austenitizing at least 30 min, tempering at least 60 min (guide values).
Source: EN 10083-1:1991 (UNI EN 10083-1), Table XIII
Active EN 10083-1:1991 2C50 Listings on M-EX (For Sale)