Steel 15X
Description
Steel 15X
Steel 15X: 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 15X.
General information about steel 15X
| Substitute brand |
| steel 20X. |
| Delivery type |
| Long products, including shaped: GOST 4543−71, GOST 2590−71, GOST 2591−71, GOST 2879−69, GOST 4693−77, GOST 10702−78. Calibrated bar GOST 7414−75, GOST 8559−75, GOST 8560−78, GOST 1051−73, GOST 10702−78. Polished bar and silver bar GOST 14955−77. Strip GOST 103−76. Forgings and forged billets GOST 8479−70, GOST 1131−71. Pipes GOST 8733−87, GOST 8734−75. |
| Application |
| bushings, pins, gears, rollers, pushers and other cemented parts, which are required to have high surface hardness with low core strength, parts operating under frictional wear conditions. |
Chemical composition of steel 15X
| Chemical element |
% |
| Silicon (Si) |
0.17−0.37 |
| Manganese (Mn) |
0.40−0.70 |
| Copper (Cu), no more |
0.30 |
| Nickel (Ni), no more |
0.30 |
| Sulfur (S), no more |
0.035 |
| Carbon (C) |
0.12−0.18 |
| Phosphorus (P), no more |
0.035 |
| Chromium (Cr) |
0.70−1.00 |
Mechanical properties of steel 15X
Mechanical properties at elevated temperatures
| test t, ° C |
σ B, MPa |
δ 10 ,% |
ψ,% |
| Sample 10 mm in diameter, 100 mm long, annealed. The movement speed of the machine grips is 0.38−0.47 mm / min. |
| 800 |
48 |
36 |
56 |
| 900 |
47 |
19 |
25 |
| 1000 |
32 |
29 |
52 |
| 1100 |
32 |
42 |
96 |
| 1150 |
19 |
52 |
98 |
Mechanical properties of rolled products
| Heat treatment, delivery condition |
σ 0.2, MPa |
σ B, MPa |
δ 5 ,% |
ψ,% |
KCU, J / m 2 |
HB |
HRC e |
| Bar. Quenching 880 ° C, water or oil, quenching 770−820 ° C, water or oil, tempering 180 ° C, air or oil |
490 |
690 |
12 |
45 |
64 |
|
|
| Calibrated and calibrated steel with special finishing after annealing or tempering |
|
550 |
|
60 |
|
179 |
|
| Calibrated and calibrated steel with special finishing after spheroidizing annealing |
|
340−440 |
|
60 |
|
179 |
|
| Steel calibrated and calibrated with a special finish, work-hardened without heat treatment |
|
590 |
five |
45 |
|
207 |
|
| Bar. Cementation 910 ° С, quenching 790 ° С, water, tempering 190 ° С. |
370 |
610 |
fifteen |
45 |
59 |
179 |
58−64 |
Mechanical properties of forgings
| Heat treatment, delivery condition |
Section, mm |
σ 0.2, MPa |
σ B, MPa |
δ 5 ,% |
ψ,% |
KCU, J / m 2 |
HB |
| Normalization |
| KP 195 |
<100 |
195 |
390 |
26 |
55 |
59 |
111−156 |
| KP 195 |
100−300 |
195 |
390 |
23 |
50 |
54 |
111−156 |
| Quenching, tempering |
| KP 345 |
<100 |
345 |
590 |
eighteen |
45 |
59 |
174−217 |
Mechanical properties depending on the tempering temperature
| vacation t, ° С |
σ 0.2, MPa |
σ B, MPa |
δ 5 ,% |
ψ,% |
KCU, J / m 2 |
| Hardening 880 ° C. |
| 200 |
550 |
780 |
7 |
46 |
39 |
| 300 |
560 |
750 |
4 |
55 |
49 |
| 400 |
560 |
720 |
6 |
59 |
78 |
| 500 |
540 |
680 |
nine |
61 |
98 |
| 600 |
530 |
630 |
ten |
61 |
127 |
Technological properties of steel 15X
| Forging temperature |
| Beginning 1260, end 800. Billets with a section up to 200 mm are cooled in air, 200−700 mm are subjected to low-temperature annealing. |
| Weldability |
| welded without restrictions (except for chemically-thermally treated parts). Welding methods: RDS, KTS without restrictions. |
| Machinability by cutting |
| at σ B = 730 MPa K υ tv.spl. = 1,0, K υ b.st. = 0.9. |
| Tendency to release ability |
| not inclined |
| Flock sensitivity |
| not sensitive |
Temperature of critical points of steel 15X
| Critical point |
° C |
| Ac1 |
766 |
| Ac3 |
838 |
| Ar3 |
799 |
| Ar1 |
702 |
Impact strength of steel 15X
Impact strength, KCU, J / cm 2
| Delivery status, heat treatment |
+20 |
-40 |
| Sample after quenching at 850 C, oil, tempering at 200 C, 1 h. |
98 |
61 |
Hardenability of steel 15X
Hardness for strips HRCe.
| Distance from the end, mm / HRC e |
| 1.5 |
3 |
4.5 |
6 |
7.5 |
nine |
10.5 |
12 |
13.5 |
fifteen |
| 36−44.5 |
32−44.5 |
25−42.5 |
38.5 |
33 |
29 |
26 |
24.5 |
23 |
22 |
Physical properties of steel 15X
| Test temperature, ° С |
20 |
100 |
200 |
300 |
400 |
500 |
600 |
700 |
800 |
900 |
| Normal elastic modulus, E, GPa |
215 |
212 |
194 |
191 |
179 |
170 |
162 |
142 |
132 |
|
| Torsional shear elastic modulus G, GPa |
83 |
82 |
76 |
74 |
71 |
67 |
63 |
55 |
50 |
|
| Density of steel, pn, kg / m 3 |
7830 |
7810 |
7780 |
|
7710 |
|
7640 |
|
|
|
| Thermal conductivity coefficient W / (m ° С) |
44 |
44 |
43 |
41 |
39 |
36 |
33 |
32 |
32 |
|
| 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) |
10.2 |
11.5 |
12.4 |
13.0 |
13.5 |
14.0 |
|
|
|
|
| Specific heat (C, J / (kg ° C)) |
496 |
508 |
525 |
538 |
567 |
588 |
626 |
706 |
|
|