Steel 20KHGNR
Description
Steel 20KHGNR
Steel 20KHGNR: a brand of steels and alloys. Below is a 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 20HGNR.
General information about steel 20ХГНР
Substitute brand |
steel: 20ХН3А, 12ХН2, 12ХН3А. |
Delivery type |
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. Pipes OST 14−21−77. |
Application |
Gear wheels, pinion shafts, worms, cam couplings, bushings and other critical parts operating under shock loading conditions. |
Chemical composition of steel 20HGNR
Chemical element |
% |
Boron (B) |
0.001−0.005 |
Silicon (Si) |
0.17−0.37 |
Manganese (Mn) |
0.70−1.00 |
Copper (Cu), no more |
0.30 |
Nickel (Ni) |
0.80−1.10 |
Sulfur (S), no more |
0.035 |
Titanium (Ti), no more |
0.06 |
Carbon (C) |
0.16−0.23 |
Phosphorus (P), no more |
0.035 |
Chromium (Cr) |
0.70−1.10 |
Mechanical properties of steel 20HGNR
Mechanical properties at elevated temperatures
test t, ° C |
σ 0.2, MPa |
σ B, MPa |
δ 5 ,% |
ψ,% |
Sample 10 mm in diameter, 50 mm long, rolled. Deformation rate 20 mm / min. Strain rate 0.007 1 / s. |
800 |
115 |
12 |
41 |
84 |
900 |
73 |
81 |
47 |
100 |
1000 |
32 |
44 |
58 |
100 |
1100 |
19 |
29 |
63 |
100 |
1200 |
fifteen |
25 |
76 |
100 |
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 860 ° C, oil. Cooling after tempering in oil. |
200 |
1250 |
1510 |
eleven |
55 |
61 |
47 |
300 |
1230 |
1400 |
8 |
50 |
62 |
47 |
400 |
1180 |
1240 |
eleven |
58 |
69 |
43 |
500 |
970 |
970 |
fourteen |
64 |
125 |
33 |
600 |
690 |
820 |
17 |
65 |
182 |
27 |
Mechanical properties depending on the section
Section, mm |
σ 0.2, MPa |
σ B, MPa |
δ 5 ,% |
ψ,% |
KCU, J / m 2 |
HB |
Rods. Normalization 930 ° C, air. Hardening 840 ° С, oil. Vacation 200 ° C, air. |
25 |
1370 |
1420 |
fourteen |
60 |
108 |
418 |
50 |
1110 |
1200 |
12 |
62 |
147 |
340 |
75 |
970 |
1060 |
fifteen |
60 |
108 |
302 |
100 |
920 |
1000 |
fifteen |
60 |
127 |
302 |
150 |
830 |
1000 |
sixteen |
50 |
98 |
286 |
Mechanical properties of the bar
Section, mm |
σ 0.2, MPa |
σ B, MPa |
δ 5 ,% |
ψ,% |
KCU, J / m 2 |
HB |
HRC e |
Normalization 930−950 ° C, air. Hardening 780−830 ° С, oil. Vacation 200 ° C, air or oil |
fifteen |
1080 |
1270 |
ten |
50 |
88 |
|
|
Cementation 930−950 ° C. Hardening 830−850 ° С, oil. Vacation 170−230 ° С, air. |
fifteen |
1360 |
1460 |
thirteen |
60 |
118 |
|
57−63 |
25 |
1310 |
1410 |
fourteen |
64 |
127 |
|
57−63 |
50 |
1160 |
1260 |
thirteen |
64 |
127 |
340 |
57−63 |
75 |
1080 |
1140 |
12 |
60 |
127 |
321 |
57−63 |
100 |
930 |
1040 |
17 |
66 |
127 |
302 |
57−63 |
150 |
880 |
1040 |
17 |
50 |
108 |
286 |
57−63 |
Technological properties of steel 20HGNR
Forging temperature |
Beginning 1150, end 800. Sections longer than 60 mm are cooled slowly. |
Weldability |
RDS. Heating and subsequent heat treatment are recommended. |
Tendency to release ability |
inclined |
Flock sensitivity |
sensitive |
Temperature of critical points of steel 20HGNR
Critical point |
° C |
Ac1 |
740 |
Ac3 |
830 |
Ar3 |
725 |
Ar1 |
650 |
Mn |
365 |
Impact strength of steel 20KhGNR
Impact strength, KCU, J / cm 2
Delivery status, heat treatment |
+20 |
-20 |
-40 |
-60 |
-80 |
Guenching 860 C, oil. Vacation 200 С, oil. HRCе 47 |
61 |
61 |
62 |
60 |
61 |
Guenching 860 C, oil. Vacation 500 С, oil. HRCэ 33 |
125 |
110 |
120 |
117 |
89 |
Endurance limit of steel 20ХГНР
σ -1, MPa |
n |
σ B, MPa |
Heat treatment, steel condition |
590 |
1E + 7 |
1480 |
Normalization 930 C, 3 h, air. Tempering 840 C, oil. Vacation 200 С, 2 h. |
Hardenability of steel 20HGNR
Tempering 860 C.
Distance from the end, mm / HRC e |
1.5 |
3 |
4.5 |
6 |
nine |
12 |
fifteen |
21 |
27 |
39 |
43−48.5 |
43.5−49 |
43−49.5 |
42.5−49.5 |
41−49.5 |
39.5−49 |
38−48.5 |
35−47.5 |
31−45 |
26−40 |
Heat treatment |
Crit. Diam. in oil, mm |
Crete. hardness, HRCэ |
Tempering 820 C. |
100 |
39−41 |
|
50 |
40−44 |