Steel 50G2
Description
Steel 50G2
Steel 50G2: 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 50G2.
General information of steel 50G2
| Substitute brand |
| steel: 45G2, 60G. |
| 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, GOST 1051−73. Polished bar and silver bar GOST 4543−71, GOST 14955−77. Strip GOST 4543−71, GOST 103−76. Forgings and forged billets GOST 1133−71, GOST 8479−70. |
| Application |
| gears, friction discs, gear shafts and other parts subject to abrasion. |
Chemical composition of steel 50G2
| Chemical element |
% |
| Silicon (Si) |
0.17−0.37 |
| Manganese (Mn) |
1.40−1.80 |
| Copper (Cu), no more |
0.30 |
| Nickel (Ni), no more |
0.30 |
| Sulfur (S), no more |
0.035 |
| Carbon (C) |
0.46−0.55 |
| Phosphorus (P), no more |
0.035 |
| Chromium (Cr), no more |
0.30 |
Mechanical properties of steel 50G2
Mechanical properties
| Heat treatment, delivery condition |
Section, mm |
σ 0.2, MPa |
σ B, MPa |
δ 5 ,% |
ψ,% |
KCU, J / m 2 |
HB |
| Bar. Hardening 840 ° С, oil. Vacation 650 ° C, air. |
| |
25 |
420 |
730 |
eleven |
35 |
|
|
| Forgings. Normalization |
| KP 315 |
<100 |
315 |
570 |
17 |
38 |
39 |
167−207 |
| KP 315 |
133−300 |
315 |
570 |
fourteen |
35 |
34 |
167−207 |
| KP 345 |
<100 |
345 |
590 |
eighteen |
45 |
59 |
174−217 |
| KP 345 |
100−300 |
345 |
590 |
17 |
40 |
54 |
174−217 |
| KP 395 |
<100 |
395 |
615 |
17 |
45 |
59 |
187−229 |
| Normalization |
| |
80 |
|
810 |
ten |
40 |
|
241 |
| Normalization 810−830 ° С, air. Vacation 400−500 ° C, air. |
| |
300−500 |
|
680 |
12 |
thirty |
|
241 |
Mechanical properties depending on the tempering temperature
| vacation t, ° С |
σ 0.2, MPa |
σ B, MPa |
δ 10 ,% |
ψ,% |
KCU, J / m 2 |
| Hardening 820 ° С, oil. Excerpt after tempering 30 min, cooling in oil. |
| 400 |
1200 |
1320 |
five |
37 |
68 |
| 500 |
980 |
1130 |
12 |
43 |
137 |
| 600 |
680 |
830 |
fifteen |
57 |
235 |
Technological properties of steel 50G2
| Forging temperature |
| The beginning is 1200, the end is 750−800. Billets with a cross section of up to 100 mm are cooled in air, 101−200 mm — in a mold, 201−300 mm — in a closed mold. |
| Weldability |
| not applicable for welded structures. |
| Tendency to release ability |
| inclined |
| Flock sensitivity |
| insensitive |
Temperature of critical points of steel 50G2
| Critical point |
° C |
| Ac1 |
710 |
| Ac3 |
660 |
| Ar3 |
680 |
| Ar1 |
600 |
Physical properties of steel 50G2
| Test temperature, ° С |
20 |
100 |
200 |
300 |
400 |
500 |
600 |
700 |
800 |
900 |
| Normal elastic modulus, E, GPa |
204 |
|
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| Torsional shear elastic modulus G, GPa |
83 |
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| Density of steel, pn, kg / m 3 |
7500 |
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| Thermal conductivity coefficient W / (m ° С) |
|
41 |
40 |
38 |
36 |
35 |
|
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| 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) |
11.3 |
12.2 |
12.3 |
|
|
14.7 |
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