Steel 38KH2N2MA
Description
Steel 38KH2N2MA
Steel 38Х2Н2МА: brand of steels and alloys. Below is the systematized information on the purpose, chemical composition, types of supplies, substitutes, temperature of critical points, physical, mechanical, technological and casting properties for the brand — Steel 38X2H2MA.
General information about steel 38X2H2MA
Delivery type |
Circle 38x2n2ma, long products, including shaped: GOST 4543−71, GOST 2590−71, GOST 2591−71, GOST 2879−69. Calibrated bar GOST 7417−75, GOST 8559−75, GOST 8560−78, GOST 1051−73. Polished bar and silver bar GOST 14955−77. Strip GOST 103−76. Forgings and forged billets GOST 1133−71, GOST 8479−70. Pipes OST 14−21−77. |
Application |
Shafts, connecting rods, bolts, studs and other large, especially critical, heavy-loaded parts of complex configuration, used in an improved condition. |
Chemical composition of steel 38X2H2MA
Chemical element |
% |
Silicon (Si) |
0.17−0.37 |
Manganese (Mn) |
0.25−0.50 |
Copper (Cu), no more |
0.30 |
Molybdenum (Mo) |
0.20−0.30 |
Nickel (Ni) |
1.30−1.70 |
Sulfur (S), no more |
0.025 |
Carbon (C) |
0.33−0.40 |
Phosphorus (P), no more |
0.025 |
Chromium (Cr) |
1.30−1.70 |
Mechanical properties of steel 38Х2Н2МА
Mechanical properties
Heat treatment, delivery condition |
σ 0.2, MPa |
σ B, MPa |
δ 5 ,% |
ψ,% |
KCU, J / m 2 |
HB |
Bar. Hardening 870 ° С, oil. Vacation 580 ° C, air or oil. |
|
930 |
1080 |
12 |
50 |
78 |
|
Forgings. Hardening. Vacation. |
KP 440 |
440 |
635 |
eleven |
thirty |
39 |
197−235 |
KP 735 |
735 |
880 |
thirteen |
40 |
59 |
277−321 |
KP 785 |
785 |
930 |
12 |
40 |
59 |
293−331 |
Mechanical properties depending on the tempering temperature
vacation t, ° С |
σ 0.2, MPa |
σ B, MPa |
δ 5 ,% |
ψ,% |
KCU, J / m 2 |
HRC e |
Hardening 850 ° С, oil. |
200 |
1520 |
1810 |
eleven |
46 |
44 |
53 |
300 |
1420 |
1630 |
ten |
45 |
37 |
49 |
400 |
1350 |
1470 |
ten |
46 |
39 |
46 |
500 |
1190 |
1240 |
thirteen |
55 |
68 |
40 |
600 |
880 |
960 |
17 |
64 |
137 |
32 |
Mechanical properties depending on the section
Heat treatment, delivery condition |
Section, mm |
σ 0.2, MPa |
σ B, MPa |
δ 5 ,% |
δ 10 ,% |
ψ,% |
KCU, J / m 2 |
Hardening 860 ° C, oil. Vacation 560 ° С, water |
Sample cutting location — center |
thirty |
860 |
1000 |
19 |
|
64 |
137 |
Sample cutting location — center |
50 |
830 |
970 |
sixteen |
|
61 |
144 |
Sample cutting location — center |
80 |
750 |
900 |
eighteen |
|
61 |
150 |
Sample cutting location — center |
120 |
740 |
900 |
19 |
|
60 |
144 |
Sample cutting location — edge |
120 |
770 |
940 |
eighteen |
|
61 |
151 |
Sample cutting location — center |
200 |
750 |
900 |
17 |
|
52 |
66 |
Sample cutting location — edge |
200 |
770 |
930 |
17 |
|
57 |
72 |
Hire. Hardening 950 ° С, oil. Vacation 580−600 ° C. |
Sample cutting location — center |
500 |
760 |
930 |
|
fifteen |
52 |
57 |
Sample cutting location — edge |
500 |
770 |
960 |
|
17 |
55 |
53 |
The sample is cut in the center. Cross samples |
500 |
740 |
930 |
|
eleven |
|
23 |
The sample was cut out at the edge. Cross samples |
500 |
760 |
930 |
|
eleven |
23 |
22 |
Sample cutting location — center |
700 |
740 |
900 |
|
17 |
51 |
45 |
Sample cutting location — edge |
700 |
740 |
930 |
|
17 |
52 |
|
The sample is cut in the center. Cross samples |
700 |
790 |
900 |
|
|
|
fifteen |
The sample was cut out at the edge. Cross samples |
700 |
730 |
880 |
|
eleven |
20 |
57 |
Sample cutting location — center |
900 |
710 |
850 |
|
7 |
sixteen |
26 |
Sample cutting location — edge |
900 |
700 |
890 |
|
sixteen |
49 |
46 |
The sample is cut in the center. Cross samples |
900 |
690 |
730 |
|
|
6 |
20 |
The sample was cut out at the edge. Cross samples |
900 |
700 |
870 |
|
eleven |
22 |
24 |
Technological properties of steel 38Х2Н2МА
Forging temperature |
Start 1200, end 800. Cooling is slow. |
Weldability |
not applicable for welded structures. |
Tendency to release ability |
not inclined |
Flock sensitivity |
sensitive |
Temperature of critical points of steel 38X2H2MA
Critical point |
° C |
Ac1 |
753 |
Ac3 |
790 |
Ar3 |
490 |
Ar1 |
370 |
Mn |
320 |
Impact strength of steel 38X2H2MA
Impact strength, KCU, J / cm 2
Delivery status, heat treatment |
+20 |
-40 |
-50 |
Blanks with a cross section of 30 mm. Guenching 860 C, oil. Vacation 560 С, water. |
137 |
129 |
122 |
Workpieces with a cross section of 50 mm |
144 |
138 |
112 |
Workpieces with a section of 80 mm |
150 |
93 |
85 |
Workpieces with a section of 120 mm |
144 |
76 |
73 |
Workpieces with a section of 200 mm |
66 |
34 |
|
Endurance limit of steel 38X2H2MA
σ -1, MPa |
n |
σ B, MPa |
σ 0.2, MPa |
363 |
5E + 6 |
|
880 |
300 |
5E + 6 |
720 |
520 |
Hardenability of steel 38Х2Н2МА
Hardening 845 C. Hardness for strips of hardenability HRCe.
Distance from the end, mm / HRC e |
1.5 |
3 |
five |
nine |
thirteen |
20 |
25 |
thirty |
40 |
50 |
51.5−59 |
51.5−59 |
50.5−59 |
49.5−58 |
49.5−58 |
47.5−57 |
46.5−57 |
45.5−56 |
44.5−56 |
42.5−56 |
Crit. Diam. in oil, mm |
Crete. hardness, HRCэ |
100 |
53 |
Short-term thermal strength of steel 38Х2Н2МА
Test temperature, ° С |
s 0.2, MPa |
σ B, MPa |
d 5 ,% |
y,% |
100 |
820 |
930 |
17 |
64 |
200 |
860 |
910 |
sixteen |
64 |
300 |
730 |
880 |
sixteen |
65 |
400 |
690 |
780 |
eighteen |
73 |
500 |
570 |
620 |
22 |
80 |
600 |
340 |
400 |
35 |
82 |
Physical properties of steel 38Х2Н2МА
Test temperature, ° С |
20 |
100 |
200 |
300 |
400 |
500 |
600 |
700 |
800 |
900 |
Normal elastic modulus, E, GPa |
213 |
206 |
194 |
180 |
174 |
164 |
157 |
141 |
129 |
|
Torsional shear elastic modulus G, GPa |
84 |
80 |
76 |
71 |
67 |
63 |
59 |
59 |
48 |
|
Thermal conductivity coefficient W / (m ° С) |
38 |
37 |
35 |
35 |
33 |
32 |
thirty |
28 |
28 |
|
Ud. electrical resistance (p, Nom. m) |
322 |
398 |
482 |
592 |
740 |
910 |
1090 |
1300 |
|
|
Test temperature, ° С |
20−100 |
20−200 |
20−300 |
20−400 |
20−500 |
20−600 |
20−700 |
20−800 |
20−900 |
20−1000 |
Linear expansion coefficient (a, 10−6 1 / ° С) |
11.9 |
12.5 |
13.1 |
13.3 |
13.8 |
14.1 |
14.6 |
11.8 |
|
|
Specific heat (C, J / (kg ° C)) |
490 |
502 |
523 |
532 |
565 |
560 |
615 |
670 |
|
|