NITRIDING STEELS: CORRESPONDENCE OF DIFFERENT NORMS

UNI

EU

DIN

AFNOR

BS

SAE

GOST

31CrMo12

31CrMoV12

34CrAlMo7

41CrAlMo7

31CrMo12

 

41CrAlMo7

31CrMo12 (1.8515)

31CrMoV9 (1.8519)

34CrAlMo5 (1.8507)

38CrAlMo7 (1.8509)

30CD12

 

30CAD6.12

40CAD6.12

722M24

 

90SM31

90SM39

 

J24056

 

38ChMJuA

--

--

15CrMoV5.9 1.8521

34CrAlNi7 1.8550

--

--

--

--

CHEMICAL ANALYSIS % ON THE PRODUCT

Steel

C

Mn

Si

P

S

Cr

Mo

V

Al

Ni

31CrMo12

31CrMoV10

34CrAlMo7

41CrAlMo7

31CrMoV9

15CrMoV5.9

34CrAlMo5

0.27÷0.36

0.28÷0.36

0.29÷0.38

0.38÷0.45

0.26÷0.34

0.13÷0.18

0.30÷0.37

0.36÷0.74

0.36÷0.74

0.46÷0.84

0.46÷0.84

0.40÷0.70

0.80÷1.10

0.50÷0.80

0.12÷0.43

0.12÷0.43

0.17÷0.53

0.17÷0.53

0.40 max

0.40 max

0.40 max

0.035max

0.035max

0.035max

0.035max

0.025max

0.025max

0.025max

0.035max

0.035max

0.035max

0.035max

0.030max

0.030max

0.030max

2.70÷3.30

2.20÷2.90

1.45÷1.85

1.45÷1.85

2.30÷2.70

1.20÷1.50

1.00÷1.30

0.27÷0.43

0.27÷0.43

0.22÷0.43

0.22÷0.43

0.15÷0.25

0.80÷1.10

0.15÷0.25

 

0.08÷0.22

 

 

0.10÷0.20

0.20÷0.30

 

 

0.70÷1.30

0.70÷1.30

 

 

0.80÷1.20

--

34CrAlNi7

0.30÷0.37

0.40÷0.70

0.40 max

0.025max

0.030max

1.50÷1.80

0.15÷0.25

--

0.80÷1.20

0.85÷1.15

MECHANICAL CHARACTERISTICS OF NITRIDING STEELS WHEN HARDENED AND TEMPERED (longitudinal specimen taken at 12.5 mm from the surface)

Steel

Diameter or thickness

Breaking load per unit N/mm2

Load proportional deviation per unit Rp02

Minimum As Extension %

Impact strength KCU Minimum J

Hardness HB N/mm2

31CrMo12





31CrMoV10




34CrAlMo7

41CrAlMo7


31CrMoV9


15CrMoV5.9


34CrAlMo5

0 - 16
16 - 40
40 - 100
100 - 160
160 - 250

0 - 16
16 - 40
40 - 100
100 - 160

0 - 70

0 - 100
100 - 160

0 - 100
100 - 250

0 - 100
100 - 250

0 - 70

1080÷1275
1030÷1225
980÷1180
930÷1130
880÷1080

1030÷1225
930÷1080
885÷1030
835÷980

785÷930

930÷1130
835÷980

1000÷1200
900÷1100

900÷1100
850÷1050

800÷1000

min. 880
min.835
min.785
min.735
min. 685

min. 835
min. 785
min. 735
min. 710

min. 590

min. 735
min. 740

min. 800
min. 700

min. 750
min. 700

min. 600

10
10
11
12
12

12
13
14
15

14

12
14

11
12

10
12

14

24.5
29.5
29.5
29.5
29.5

34.5
31.5
32.0
32.0

24.5

19.5
22.5

40
50

35
40

40

330÷386
316÷371
300÷358
284÷344
268÷330

316÷371
284÷330
270÷316
257÷300

242÷284

284÷344
257÷300

298÷360
266÷325

266÷325
250÷310

238÷298

34CrAlNi7

0 - 100

100 - 250

850÷1050

800÷1000

min. 650

min. 600

12

13

35

40

250÷310

238÷298