Steel 20ХН2М (20ХНМ)
Description
Steel 20ХН2М (20ХНМ)
Steel 20ХН2М (20ХНМ): 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 grade — Steel 20ХН2М (20ХНМ).
General information about steel 20ХН2М (20ХНМ)
| Substitute brand |
| steel: 20HGR, 15HR, 20HNR, 25HGNR. |
| Delivery type |
| Long products, including shaped: GOST 4543−71, GOST 2590−71, GOST 2591−71, GOST 2879−69. Calibrated bar GOST 4543−71, GOST 7417−75, GOST 8559−75, GOST 8560−78. Polished bar and silver bar GOST 14955−77, GOST 4543−71. Strip GOST 103−76. Forgings and forged billets GOST 4543−71, GOST 1133−71. Pipes OST 14−21−77. |
| Application |
| Gears, axle shafts, satellites, cams, hinges and other parts. |
Chemical composition of steel 20ХН2М (20ХНМ)
| Chemical element |
% |
| Silicon (Si) |
0.17−0.37 |
| Manganese (Mn) |
0.40−0.70 |
| Copper (Cu), no more |
0.30 |
| Molybdenum (Mo) |
0.20−0.30 |
| Nickel (Ni) |
1.60−2.00 |
| Sulfur (S), no more |
0.035 |
| Carbon (C) |
0.15−0.22 |
| Phosphorus (P), no more |
0.035 |
| Chromium (Cr) |
0.40−0.60 |
Mechanical properties of steel 20ХН2М (20ХНМ)
Mechanical properties depending on the tempering temperature
| vacation t, ° С |
σ 0.2, MPa |
σ B, MPa |
δ 5 ,% |
ψ,% |
KCU, J / m 2 |
| Transverse samples. Hardening 860 ° C, malso. Exposure on vacation 2 h. |
| 200 |
1210 |
1420 |
five |
21 |
38 |
| 600 |
970 |
1010 |
12 |
42 |
52 |
Mechanical properties versus test temperature
| Section, mm |
test t, ° C |
σ 0.2, MPa |
σ B, MPa |
δ 5 ,% |
ψ,% |
KCU, J / m 2 |
| Transverse samples. Hardening 860 ° C, oil. Vacation 200 ° С, 2 h, air. |
| eleven |
20 |
1210 |
1420 |
five |
21 |
38 |
| 8 |
-40 |
1260 |
1470 |
4 |
21 |
|
| 8 |
-70 |
1280 |
1480 |
4 |
21 |
|
| Transverse samples. Hardening 860 ° C, oil. Vacation 600 ° C, 2 h, air. |
| eleven |
20 |
970 |
1010 |
12 |
42 |
52 |
| 8 |
-40 |
1010 |
1060 |
eleven |
27 |
|
| 8 |
-70 |
1030 |
1090 |
eleven |
23 |
|
Mechanical properties of the bar
| Section, mm |
σ 0.2, MPa |
σ B, MPa |
δ 5 ,% |
ψ,% |
KCU, J / m 2 |
HB |
HRC e |
| Hardening 860 ° C, oil. Hardening 780 ° С, oil. Vacation 200 ° C, water or oil. |
| fifteen |
685 |
880 |
eleven |
50 |
78 |
|
|
| Cementation 930−950 ° С, air. Hardening 810−830 ° С, oil. Vacation 180−200 ° C, air. |
| <30 |
930 |
1180 |
eleven |
50 |
78 |
341 |
57−63 |
| 30−50 |
830 |
1080 |
ten |
40 |
59 |
250−320 |
57−63 |
Technological properties of steel 20ХН2М (20ХНМ)
| Forging temperature |
| Beginning 1200, end 800. For workpieces with a cross section of more than 60 mm, slow cooling. |
| Weldability |
| RDS with heating and subsequent heat treatment. |
| Tendency to release ability |
| not inclined |
| Flock sensitivity |
| sensitive |
Temperature of critical points of steel 20ХН2М (20ХНМ)
| Critical point |
° C |
| Ac1 |
720 |
| Ac3 |
825 |
Impact strength of steel 20ХН2М (20ХНМ)
Impact strength, KCU, J / cm 2
| Delivery status, heat treatment |
+20 |
-40 |
-70 |
| Workpieces with a cross section of 11 mm. Guenching 860 C, oil. Vacation at a temperature of 300 C, 2 hours. |
75 |
50 |
37 |
| Workpieces with a cross section of 11 mm. Guenching 860 C, oil. Vacation at a temperature of 400 C, 2 hours |
87 |
63 |
54 |
| Workpieces with a cross section of 11 mm. Guenching 860 C, oil. Vacation at a temperature of 500 C, 2 hours |
158 |
84 |
63 |
Hardenability of steel 20ХН2М (20ХНМ)
Hardening 810 C. Hardness for strips of hardenability HRCe.
| Distance from the end, mm / HRC e |
| 4 |
6 |
12 |
eighteen |
24 |
thirty |
36 |
48 |
| 35.5−46.5 |
35−46.5 |
27−38.5 |
22−34 |
21−30 |
20.5−29.5 |
19.5−29.5 |
28 |
