Steel 30KHGS
Description
Steel 30KHGS
Steel 30KhGS: 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 30HGS.
General information about steel 30HGS
| Substitute brand |
| Steel 40KHFA, 35KHM, 40KHN, 35KHGSA. |
| Delivery type |
| Long products, including shaped: GOST 4543−71, GOST 259071, GOST 2591−71. Calibrated bar GOST 7417−75, GOST 8559−75, GOST 8560−78, GOST 1051−73. Polished bar and silver bar GOST 4543−71, GOST 14955−77. Thin sheet 1542−71. Strip GOST 103−76. Forgings and forged billets GOST 1133−71, GOST 8479−70. Pipes OST 14−21−77. |
| Application |
| Various upgradable parts: shafts, axles, gear wheels, brake bands of motors, flanges, casing housings, compressor blades, levers, pushers, critical welded structures operating under alternating loads, fasteners. |
Chemical composition of steel 30HGS
| Chemical element |
% |
| Silicon (Si) |
0.90−1.20 |
| Manganese (Mn) |
0.80−1.10 |
| Copper (Cu), no more |
0.30 |
| Nickel (Ni), no more |
0.30 |
| Sulfur (S), no more |
0.035 |
| Carbon (C) |
0.28−0.35 |
| Phosphorus (P), no more |
0.035 |
| Chromium (Cr) |
0.80−1.10 |
Mechanical properties of steel 30HGS
| Heat treatment, delivery condition |
Section, mm |
σ 0.2, MPa |
σ B, MPa |
δ 5 ,% |
ψ,% |
KCU, J / m 2 |
HRC e |
| Hardening 880 ° С, oil. Vacation 540 ° C, water or oil |
25 |
830 |
1080 |
ten |
45 |
44 |
|
| Forgings. Normalization. KP 395 |
<100 |
395 |
615 |
17 |
45 |
59 |
|
| Hardening 860−880 ° С, oil. Vacation 200−250 ° С, air. |
thirty |
1270 |
1470 |
7 |
40 |
|
43−51 |
| Hardening 860−880 ° С, oil. Vacation 540−560 ° C, water or oil. |
60 |
690 |
880 |
nine |
45 |
59 |
|
Mechanical properties at elevated temperatures
| test t, ° C |
σ 0.2, MPa |
σ B, MPa |
δ 5 ,% |
ψ,% |
KCU, J / m 2 |
| Hardening 880 ° С, oil. Vacation 560 ° С, air. |
| 20 |
950 |
1050 |
thirteen |
56 |
52 |
| 250 |
840 |
1000 |
thirteen |
48 |
126 |
| 300 |
820 |
950 |
eleven |
50 |
124 |
| 400 |
780 |
900 |
sixteen |
69 |
94 |
| 500 |
650 |
690 |
21 |
84 |
72 |
| Sample 5 mm in diameter and 25 mm long. Laminated. Strain rate 2 mm / min, strain rate 0.0013 1 / s |
| 700 |
|
175 |
59 |
51 |
|
| 800 |
|
85 |
62 |
75 |
|
| 900 |
|
53 |
84 |
> 90 |
|
| 1000 |
|
37 |
71 |
> 90 |
|
| 1100 |
|
21 |
59 |
> 90 |
|
| 1200 |
|
ten |
85 |
> 90 |
|
Mechanical properties depending on the tempering temperature
| vacation t, ° С |
σ 0.2, MPa |
σ B, MPa |
δ 5 ,% |
ψ,% |
KCU, J / m 2 |
| Bar with a diameter of 20−70 mm. Hardening 880 ° С, oil. |
| 200 |
1570 |
1700 |
eleven |
44 |
88 |
| 300 |
1520 |
1630 |
eleven |
54 |
69 |
| 400 |
1320 |
1420 |
12 |
56 |
49 |
| 500 |
1140 |
1220 |
fifteen |
56 |
78 |
| 600 |
940 |
1040 |
19 |
62 |
137 |
Mechanical properties depending on the section
| Section, mm |
σ 0.2, MPa |
σ B, MPa |
δ 5 ,% |
ψ,% |
KCU, J / m 2 |
HB |
| Hardening 880 ° С, oil. Vacation 600 ° C, water. |
| 40 |
820 |
930 |
12 |
51 |
69 |
275 |
| 80 |
730 |
860 |
fourteen |
50 |
78 |
250 |
| 120 |
670 |
820 |
fourteen |
50 |
78 |
235 |
| 160 |
580 |
750 |
fourteen |
50 |
78 |
210 |
| 180 |
510 |
710 |
thirteen |
45 |
49 |
200 |
Technological properties of steel 30HGS
| Forging temperature |
| Beginning 1240, end 800. Sections up to 50 mm are cooled in stacks in air, 51−100 mm — in boxes. |
| Weldability |
| restrictedly weldable. Welding methods: RDS, ADS submerged arc and gas shielded, ArDS, EShS. Heating and subsequent heat treatment is recommended, KTS without restrictions. |
| Machinability by cutting |
| In the hot-rolled state at HB 207−217 σ B = 710 MPa K υ tv.spl. = 0.85, K υ b.st. = 0.75. |
| Tendency to release ability |
| inclined |
| Flock sensitivity |
| sensitive |
Temperature of critical points of steel 30HGS
| Critical point |
° C |
| Ac1 |
760 |
| Ac3 |
830 |
| Ar3 |
705 |
| Ar1 |
670 |
| Mn |
352 |
Impact strength of steel 30HGS
Impact strength, KCU, J / cm 2
| Delivery status, heat treatment |
+20 |
-20 |
-40 |
-60 |
-80 |
| Tempering 880 C, oil. Vacation 580−600 C, bw = 1000 MPa. |
69 |
55 |
41 |
34 |
23 |
Endurance limit of steel 30HGS
| σ -1, MPa |
τ -1, MPa |
n |
σ B, MPa |
Heat treatment, steel condition |
| 696 |
|
|
|
Tempering 870 C. Tempering 200 C |
| 637 |
|
|
|
Tempering 870 C. Tempering 400 C |
| 470 |
|
|
|
Tempering 870 C. Tempering 600 C |
| 490 |
1666 |
1E + 7 |
1660 |
Quenching 870−890 C. Tempering 200 C |
| 372 |
882 |
1E + 7 |
880 |
Quenching 870−890 С. Tempering 600 С |
Hardenability of steel 30HGS
Hardening 800 C. Hardness for hardenability strips HRCe.
| Distance from the end, mm / HRC e |
| 1.5 |
3 |
4.5 |
6 |
nine |
12 |
fifteen |
eighteen |
21 |
24 |
| 50.5−55 |
49−54 |
47.5−53 |
46−52.5 |
41.5−52 |
38−51 |
36.5−48.5 |
35.5−46.5 |
33−44.5 |
30−43 |
| Amount of martensite,% |
Crit. Diam. in water, mm |
Crit. Diam. in oil, mm |
Crete. hardness, HRCэ |
| 50 |
60−91 |
34−60 |
37−42 |
| 90 |
40−68 |
18−40 |
43−48 |
Physical properties of steel 30HGS
| Test temperature, ° С |
20 |
100 |
200 |
300 |
400 |
500 |
600 |
700 |
800 |
900 |
| Normal elastic modulus, E, GPa |
194 |
185 |
173 |
169 |
166 |
156 |
|
|
|
|
| Torsional shear elastic modulus G, GPa |
84 |
82 |
79 |
75 |
71 |
66 |
62 |
54 |
47 |
|
| Density of steel, pn, kg / m 3 |
7850 |
7830 |
7800 |
7760 |
7730 |
7700 |
7670 |
|
|
|
| Thermal conductivity coefficient W / (m ° С) |
|
37 |
41 |
38 |
37 |
36 |
35 |
34 |
32 |
|
| Ud. electrical resistance (p, Nom. m) |
210 |
|
|
|
|
|
|
|
|
|
| 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) |
12.0 |
12.5 |
12.9 |
13.2 |
13.6 |
13.9 |
|
|
|
|
| Specific heat (C, J / (kg ° C)) |
493 |
504 |
512 |
533 |
554 |
584 |
622 |
693 |
|
|