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25CrMo4
EN 10083-3:2002, Number: 1.7218
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|
Comparison of steel grades
|
|
JUS
|
Č.4730
|
|
DIN
|
25CrMo4
|
|
BS
|
708 M 25, 708 A 25
|
|
GOST
|
20HM, 30HM
|
|
AISI
|
5140
|
|
UNI
|
25CrMo4
|
|
NF
|
25 CD 4, 25CrMo4
|
Chemical analysis -% by mass
|
Chemical elements
|
C
|
Si
|
Mn
|
P
|
S
|
Cr
|
Mo
|
|
%, by mass
|
0,22 - 0,29
|
£ 0,40
|
0,60 - 0,90
|
max 0.025
|
max 0,035
|
0,90-1,20
|
0,15-0,30
|
|
Permissible deviation
|
± 0.02
|
± 0,03
|
± 0,04
|
+ 0.005
|
+ 0.005
|
± 0.05
|
± 0.03
|
Mechanical properties in the
quenched and tempered condition
|
|
d ≤ 16mm oder
t ≤ 8mm
|
16mm < d ≤ 40mm
8mm < t ≤
20mm
|
40mm < d ≤
100mm
20mm < t ≤
60mm
|
100mm < d
≤ 160mm
60mm < t ≤
100mm
|
160mm < d ≤
250mm
100mm < t
≤ 160mm
|
|
Re min (MPa)
|
700
|
600
|
450
|
400
|
-
|
|
Rm (MPa)
|
900-1100
|
800-950
|
700-850
|
650-800
|
-
|
|
A min. (%)
|
12
|
14
|
15
|
16
|
-
|
|
Z min. (%)
|
45
|
55
|
60
|
60
|
-
|
|
KV min. (J)
|
50
|
50
|
50
|
45
|
-
|
Jominy’s hardenability band
|
Distance in mm from quenched end
Hardness in HRC
(mm)
|
|
mm
|
1,5
|
3
|
5
|
7
|
9
|
11
|
13
|
15
|
20
|
25
|
30
|
35
|
40
|
45
|
50
|
|
+H
|
max.
|
52
|
52
|
51
|
50
|
48
|
46
|
43
|
41
|
37
|
35
|
33
|
32
|
31
|
31
|
31
|
|
min.
|
44
|
43
|
40
|
37
|
34
|
31
|
29
|
27
|
23
|
21
|
20
|
-
|
-
|
-
|
-
|
|
+HH*
|
max.
|
52
|
52
|
51
|
50
|
48
|
46
|
43
|
41
|
37
|
35
|
33
|
32
|
31
|
31
|
31
|
|
min.
|
47
|
46
|
44
|
41
|
39
|
37
|
34
|
32
|
28
|
26
|
24
|
23
|
22
|
22
|
22
|
|
+HL*
|
max.
|
49
|
49
|
47
|
47
|
43
|
41
|
38
|
36
|
32
|
30
|
29
|
28
|
27
|
27
|
27
|
|
min.
|
44
|
43
|
40
|
37
|
34
|
31
|
29
|
27
|
23
|
21
|
20
|
-
|
-
|
-
|
-
|
Heat treatment conditions –
informative
|
Hardening temperature
in the end quench test
|
Quenching temperature
|
Quenching in
|
Tempering temperature
|
|
8500±50C
|
840-900 0C
|
Water or oil
|
540-680 0C
|
Maximum hardness for products to be
supplied in the ’’treated to improve shearability (+S)’’ or
’’soft annealed (+A)’’ condition
|
+S
HB max.
|
+A
HB max.
|
|
255
|
212
|
|
25CrMo4
EN 10250-3:1999, Number: 1.7218
|
|
Comparison of steel grades
|
|
JUS
|
Č.4730
|
|
DIN
|
25CrMo4
|
|
BS
|
708 M 25, 708 A 25
|
|
GOST
|
20HM, 30HM
|
|
AISI
|
5140
|
|
UNI
|
25CrMo4
|
|
NF
|
25 CD 4, 25CrMo4
|
Chemical analysis -% by mass *
|
Chemical elements
|
C
|
Si
|
Mn
|
P
max.
|
S
max.
|
Cr
|
Mo
|
-
|
-
|
|
%, by mass
|
0,22 - 0,29
|
£ 0,40
|
0,60 - 0,90
|
0.035
|
0.035
|
0,90 -1,20
|
0,15 – 0,30
|
-
|
|
|
Permissible deviation
|
± 0,02
|
+ 0,03
|
± 0,04
|
+ 0,005
|
+ 0,005
|
± 0,05
|
± 0,03
|
-
|
-
|
* At
the option the manufacturer the elements aluminium, titanium, vanadium and
niobium may be added singly or in combination for grain control
purposes. Elements not quoted in tables shall not be added intentionally to
the steel without the agreement of the purchaser, except for the purpose
of finishing the heat.
Mechanical properties in the
quenched and tempered condition
|
Trickness of ruling
section tR
|
|
Diameter in mm
|
≤ 70mm tR
(longitudinal)
|
|
70< tR
≤160mm
|
160<tR≤330mm
|
|
Re min
(N/mm2)
|
450
|
|
400
|
380
|
|
Rm min
(N/mm2)
|
700
|
|
650
|
600
|
|
A % min.
|
l-longitudinal
|
15
|
|
17
|
18
|
|
tr - transverse
|
-
|
|
13
|
14
|
|
KV min (J)
|
l-longitudinal
|
50
|
|
45
|
38
|
|
tr - transverse
|
-
|
|
27
|
22
|
Heat treatment conditions ****
|
Quenching temperature,
0C
|
Tempering temperature, 0C
|
|
840 to 880
|
540 to 680
|
****
Quenching
from hardening may be carried out in oil, water, or water based solutions.
Caution should be observed in the use of water as a
quenching medium to avoid the risk of cracking the forgings |
 |
|
|
Zeljezara Niksic - Niksic, Montenegro
Phone: (+382) 20 234-616, (+382) 40 202 900 | Fax: (+382) 40 202-023
 | Website: www.znksteel.com
|
|
