Steel 38KHGN
Description
Steel 38KHGN
Steel 38KHGN: brand of steels and alloys. Below is a systematized information about the purpose, chemical composition, types of supplies, substitutes, temperature of critical points, physical, mechanical, technological and casting properties for the brand — Steel 38HGN.
General information about steel 38HGN
Substitute brand |
steel 38HGNM. |
Delivery type |
Long products, including shaped: GOST 4543−71, GOST 2590−71, GOST 2591−71, GOST 2879−69. Calibrated bar 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, GOST 8479−70. Pipes OST 14−21−77. |
Application |
Excavator parts, fasteners, shafts, axles, gear wheels, shackles and other critical parts that require increased strength. |
Chemical composition of steel 38HGN
Chemical element |
% |
Silicon (Si) |
0.17−0.37 |
Manganese (Mn) |
0.80−1.10 |
Copper (Cu), no more |
0.30 |
Nickel (Ni) |
0.70−1.00 |
Sulfur (S), no more |
0.035 |
Carbon (C) |
0.35−0.43 |
Phosphorus (P), no more |
0.035 |
Chromium (Cr) |
0.50−0.80 |
Mechanical properties of steel 38HGN
Mechanical properties
Heat treatment, delivery condition |
Section, mm |
σ 0.2, MPa |
σ B, MPa |
δ 5 ,% |
ψ,% |
HB |
HRC e |
Bar. Hardening 850 ° С, oil. Vacation 570 ° C, water or oil. |
|
25 |
685 |
780 |
12 |
45 |
|
|
Forgings. Hardening. Vacation. |
KP 315 |
300−500 |
315 |
570 |
12 |
thirty |
167−207 |
|
Normalization |
KP 315 |
500−800 |
315 |
570 |
eleven |
thirty |
167−207 |
|
KP 345 |
<100 |
345 |
590 |
eighteen |
45 |
174−217 |
|
Hardening. Vacation |
KP 345 |
300−500 |
345 |
590 |
fourteen |
38 |
174−217 |
|
KP 345 |
500−800 |
345 |
590 |
12 |
33 |
174−217 |
|
KP 395 |
100−300 |
395 |
615 |
fifteen |
40 |
187−229 |
|
KP 395 |
300−500 |
395 |
615 |
thirteen |
35 |
187−229 |
|
KP 395 |
500−800 |
395 |
615 |
eleven |
thirty |
187−229 |
|
KP 440 |
<100 |
440 |
635 |
sixteen |
45 |
197−235 |
|
KP 440 |
300−500 |
440 |
635 |
thirteen |
35 |
197−235 |
|
KP 490 |
<100 |
490 |
355 |
sixteen |
45 |
212−248 |
|
KP 490 |
100−300 |
490 |
355 |
thirteen |
40 |
212−248 |
|
KP 540 |
<100 |
540 |
385 |
fifteen |
45 |
223−262 |
|
KP 540 |
100−300 |
540 |
385 |
thirteen |
40 |
223−262 |
|
KP 590 |
<100 |
590 |
735 |
fourteen |
45 |
235−277 |
|
Hardening 850−870 ° С, oil. Vacation 180−200 ° C, air. |
|
40 |
1340 |
1470 |
7 |
thirty |
|
50−53 |
Hardening. Vacation 650 ° C. |
|
100 |
690 |
880 |
|
60 |
241 |
|
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, forged and annealed. The deformation rate is 5 mm / min, the deformation rate is 0.002 1 / s. |
700 |
185 |
200 |
34 |
93 |
800 |
89 |
135 |
57 |
98 |
900 |
52 |
76 |
68 |
100 |
1000 |
27 |
50 |
75 |
100 |
1100 |
eighteen |
35 |
66 |
100 |
1200 |
ten |
20 |
66 |
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 |
HB |
Hardening 850 ° С, oil. |
200 |
1580 |
1780 |
fifteen |
36 |
28 |
499 |
300 |
1470 |
1670 |
sixteen |
40 |
19 |
478 |
400 |
1290 |
1370 |
sixteen |
41 |
47 |
415 |
500 |
1150 |
1200 |
sixteen |
46 |
78 |
350 |
600 |
950 |
1040 |
19 |
54 |
157 |
269 |
Mechanical properties depending on the section
Heat treatment, delivery condition |
Section, mm |
σ 0.2, MPa |
σ B, MPa |
δ 5 ,% |
ψ,% |
KCU, J / m 2 |
HB |
Hardening 850 ° C, water or oil. Vacation 560 ° С, water. |
Sample cutting location — edge |
250 |
700 |
850 |
fifteen |
54 |
69 |
269 |
Sample cutting location — 1 / 3R |
250 |
660 |
810 |
sixteen |
51 |
64 |
255 |
Sample cutting location — center |
250 |
700 |
860 |
17 |
48 |
59 |
241 |
Sample cutting location — edge |
350 |
730 |
840 |
17 |
59 |
83 |
262 |
Sample cutting location — 1 / 3R |
350 |
660 |
800 |
sixteen |
50 |
54 |
255 |
Sample cutting location — center |
350 |
690 |
870 |
fourteen |
43 |
49 |
248 |
Sample cutting location — edge |
450 |
730 |
890 |
fifteen |
54 |
73 |
262 |
Sample cutting location — 1 / 3R |
450 |
690 |
840 |
fifteen |
47 |
49 |
248 |
Sample cutting location — center |
450 |
590 |
810 |
fifteen |
32 |
35 |
235 |
Quenching 850 ° C, through water into oil. Vacation 560 ° С, 10 hours water. |
Sample cutting location — edge |
550 |
800 |
930 |
sixteen |
52 |
69 |
275 |
Sample cutting location — 1 / 3R |
550 |
660 |
870 |
fourteen |
52 |
54 |
275 |
Sample cutting location — center |
550 |
490 |
730 |
fifteen |
thirty |
60 |
229 |
Technological properties of steel 38HGN
Forging temperature |
Beginning 1200, end 800. Sections up to 250 mm are cooled in air, 251−350 mm — in a pit. |
Weldability |
difficult to weld. Welding method: RDS. Heating and subsequent heat treatment are required. |
Machinability by cutting |
After quenching and tempering at HB 187−236 and σ B = 640 MPa K υ tv.spl. = 1.0, K υ b.st. = 0.9. |
Tendency to release ability |
inclined |
Flock sensitivity |
sensitive |
Temperature of critical points of steel 38HGN
Critical point |
° C |
Ac1 |
725 |
Ac3 |
830 |
Ar3 |
690 |
Ar1 |
600 |
Mn |
320 |
Impact strength of steel 38HGN
Impact strength, KCU, J / cm 2
Delivery status, heat treatment |
+20 |
-20 |
-40 |
-60 |
Section 200 mm. Quenching through water in air and again in water (water 2−4 min, air 1−2 min, water 2−4 min). Vacation 620−640 С. |
98 |
70 |
63 |
46 |
Hardening 850 C. Vacation 650 C. |
178 |
169 |
127 |
92 |
Endurance limit of steel 38HGN
σ -1, MPa |
σ B, MPa |
Heat treatment, steel condition |
440 |
840 |
Tempering 840 C, oil. Vacation 580 C. |