Steel 38KH2N2MA (38ХНМА)
Designation
| Name |
The value |
| Designation GOST Cyrillic |
38Х2Н2МА |
| Designation GOST Latin |
38X2H2MA |
| Transliteration |
38H2N2MA |
| The chemical elements |
38Cr2Н2Mo |
| Name |
The value |
| Designation GOST Cyrillic |
38ХНМА |
| Designation GOST Latin |
38XHMA |
| Transliteration |
38HNMA |
| The chemical elements |
38CrНMo |
Description
38KH2N2MA steel is used: for the manufacture of shafts, rods, bolts, hairpins, rings of turbogenerators and other large critical heavily loaded parts of complex configuration used in the superior condition; for the manufacture of pipes tsentrobezhnolityh for the manufacture of the coils of the tubular furnace installations production of ammonia, hydrogen, ethylene, carbon disulphide, etc., operating in the temperature range 760−1060 °C and a pressure of 3.92 MPa (40 kgf/cm2); solid-rolled rings for different purposes.
Note
Structural steel high-quality romancelatina heat-resistant and corrosion-resistant.
Standards
| Name |
Code |
Standards |
| Sheets and stripes |
В23 |
GOST 103-2006 |
| Sectional and shaped rolling |
В32 |
GOST 1051-73, GOST 4543-71, GOST 7417-75, GOST 8559-75, GOST 8560-78, GOST 14955-77, OST 1 92049-76, TU 14-1-2118-77, TU 14-11-245-88, TU 14-136-367-2008 |
| Sectional and shaped rolling |
В22 |
GOST 1133-71, GOST 8319.0-75, GOST 2590-2006, GOST 2591-2006, GOST 2879-2006 |
| Metal forming. Forgings |
В03 |
GOST 8479-70, OST 5Р.9125-84, ST ЦКБА 010-2004 |
| Bulls. Blanks. Slabs |
В31 |
OST 3-1686-90, TU 14-1-4944-90 |
| Pipes steel and connecting parts to them |
В62 |
TU 1333-047-00220302-02 |
Chemical composition
| Standard |
C |
S |
P |
Mn |
Cr |
Si |
Ni |
Fe |
Cu |
V |
Ti |
Mo |
| GOST 4543-71 |
0.33-0.4 |
≤0.025 |
≤0.025 |
0.25-0.5 |
1.3-1.7 |
0.17-0.37 |
1.3-1.7 |
The rest |
≤0.3 |
≤0.05 |
≤0.03 |
0.2-0.3 |
Fe is the basis.
GOST 4543-71 regulates the content of high-quality steel: P≤0,025%; S≤0.015%; Сu≤0.25%. When changing the alloying Mo to W, the steel has the designation 38Х2Н2ВА.
Mechanical characteristics
| Section, mm |
t отпуска, °C |
sT|s0,2, MPa |
σB, MPa |
d5, % |
d |
d10 |
y, % |
kJ/m2, кДж/м2 |
Brinell hardness number, MPa |
HRC |
| Quenching in oil from 850 °C + vacation |
| - |
200 |
1520 |
1810 |
11 |
- |
- |
46 |
432 |
- |
53 |
| - |
300 |
1420 |
1630 |
10 |
- |
- |
45 |
363 |
- |
49 |
| - |
400 |
1350 |
1470 |
10 |
- |
- |
46 |
383 |
- |
46 |
| - |
500 |
1190 |
1240 |
13 |
- |
- |
55 |
667 |
- |
40 |
| - |
600 |
880 |
960 |
17 |
- |
- |
64 |
1344 |
- |
32 |
| Ring forged in OST 1 92049-76. Quenching in oil with 855-885 °C + Vacation at 530-630 °C, air cooling or oil |
| 25 |
- |
≥890 |
≥1030 |
≥9 |
- |
- |
≥40 |
≥588 |
- |
- |
| Quenching in oil from 860 °C to + vacation at 560 °C, cooling in water (named place of clippings of sample) [130] |
| 120-200 |
- |
770 |
930 |
17 |
- |
- |
57 |
- |
- |
- |
| Quenching + tempering (forgings) |
| - |
- |
440 |
635 |
11 |
- |
- |
30 |
383 |
197-235 |
- |
| Long products (wire). Quenching in oil from 870 °C to + Vacation at 580 °C air cooling or oil |
| 25 |
- |
≥930 |
≥1080 |
≥12 |
- |
- |
≥50 |
≥765 |
- |
- |
| Quenching in oil from 860 °C to + vacation at 560 °C, cooling in water (named place of clippings of sample) [130] |
| 80-120 |
- |
770 |
940 |
18 |
- |
- |
61 |
- |
- |
- |
| Quenching + tempering (forgings) |
| - |
- |
735 |
880 |
13 |
- |
- |
40 |
579 |
277-321 |
- |
| Tsentrobezhnolityh pipe outer diameter 85-320 mm. Quenching in water or air from 1100-1150 °C |
|
- |
≥170 |
≥420 |
- |
≥30 |
- |
- |
- |
- |
- |
| Quenching in oil from 860 °C to + vacation at 560 °C, cooling in water (named place of clippings of sample) [130] |
| 120-200 |
- |
750 |
900 |
17 |
- |
- |
52 |
- |
- |
- |
| Quenching + tempering (forgings) |
| - |
- |
785 |
930 |
12 |
- |
- |
40 |
579 |
293-331 |
- |
| Quenching in oil from 860 °C to + vacation at 560 °C, cooling in water (named place of clippings of sample) [130] |
| 20-30 |
- |
860 |
1000 |
19 |
- |
- |
64 |
- |
- |
- |
| 30-50 |
- |
830 |
970 |
16 |
- |
- |
61 |
- |
- |
- |
| 50-80 |
- |
750 |
900 |
18 |
- |
- |
61 |
- |
- |
- |
| 80-120 |
- |
740 |
900 |
19 |
- |
- |
60 |
- |
- |
- |
| Quenching in oil from 950 °C to + vacation at 580-600 °C (specify the place and the cutting direction of sample) |
| 300-500 |
- |
760 |
930 |
- |
- |
11 |
23 |
- |
- |
- |
| 500-700 |
- |
730 |
880 |
- |
- |
11 |
20 |
- |
- |
- |
| 700-900 |
- |
700 |
870 |
- |
- |
11 |
22 |
- |
- |
- |
| 300-500 |
- |
770 |
960 |
- |
- |
17 |
55 |
- |
- |
- |
| 500-700 |
- |
740 |
930 |
- |
- |
17 |
52 |
- |
- |
- |
| 700-900 |
- |
700 |
890 |
- |
- |
16 |
49 |
- |
- |
- |
| 300-500 |
- |
740 |
930 |
- |
- |
11 |
- |
- |
- |
- |
| 500-700 |
- |
790 |
900 |
- |
- |
- |
- |
- |
- |
- |
| 700-900 |
- |
690 |
730 |
- |
- |
- |
6 |
- |
- |
- |
| 300-500 |
- |
760 |
930 |
- |
- |
15 |
52 |
- |
- |
- |
| 500-700 |
- |
740 |
900 |
- |
- |
17 |
51 |
- |
- |
- |
| 700-900 |
- |
710 |
850 |
- |
- |
7 |
16 |
- |
- |
- |
Description mechanical marks
| Name |
Description |
| Section |
Section |
| sT|s0,2 |
Yield strength or limit of proportionality with a tolerance for residual deformation of 0.2% |
| σB |
Limit short-term strength |
| d5 |
Elongation after rupture |
| d |
Elongation after rupture |
| d10 |
Elongation after rupture |
| y |
The relative narrowing |
| kJ/m2 |
Toughness |
| HRC |
Rockwell hardness (indenter diamond spheroconical) |
Physical characteristics
| Temperature |
Е, ГПа |
G, ГПа |
l, Вт/(м · °С) |
R, НОм · м |
a, 10-6 1/°С |
С, Дж/(кг · °С) |
| 0 |
213 |
84 |
38 |
322 |
- |
- |
| 20 |
213 |
- |
38 |
322 |
- |
- |
| 100 |
206 |
80 |
37 |
398 |
119 |
490 |
| 200 |
194 |
76 |
35 |
482 |
125 |
502 |
| 300 |
180 |
71 |
35 |
592 |
131 |
523 |
| 400 |
174 |
67 |
33 |
740 |
133 |
532 |
| 500 |
164 |
63 |
32 |
910 |
138 |
565 |
| 600 |
157 |
59 |
30 |
1090 |
141 |
560 |
| 700 |
141 |
59 |
28 |
1300 |
146 |
615 |
| 800 |
129 |
48 |
28 |
- |
146 |
615 |
| 1000 |
- |
- |
- |
- |
118 |
670 |
A description of the physical symbols
| Name |
Description |
| Е |
The normal elasticity modulus |
| G |
Modulus of elasticity shear torsion |
| r |
Density |
| l |
Coefficient of thermal conductivity |
| R |
UD. the resistivity |
| С |
Specific heat |
Technological properties
| Name |
The value |
| Weldability |
does not apply to welded structures. |
| Propensity to temper brittleness |
tend not |
| Forging temperature |
Start - 1200 °C, the end - of 800 °C. Alpigena slow. |
| Flock-sensitive sensitivity |
sensitive |