Steel 18KH2N4VA
Description
Steel 18KH2N4VA
Steel 18Kh2N4VA: brand of steels and alloys. Below is the 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 18Kh2N4VA.
General information about steel 18Х2Н4ВА
Substitute brand |
steel: 15Х2ГН2ТРА, 20Х2Н4А. |
Delivery type |
Long products, including shaped: GOST 4543−71, GOST 2590−71, GOST 2591−71, GOST 2879−69, GOST 10702−78. Calibrated bar GOST 10702−78, 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 103−76. Forgings and forged billets GOST 4543−71, GOST 1133−71, GOST 8479−70. Pipes OST 14−21−77. |
Application |
In a case-hardened and exposed state, it is used for critical parts that require high strength, toughness and wear resistance, as well as for parts subjected to high vibration and dynamic loads. Steel can be used at temperatures from -70 to 450 ° C. |
Chemical composition of steel 18Kh2N4VA
Chemical element |
% |
Tungsten (W) |
0.80−1.20 |
Silicon (Si) |
0.17−0.37 |
Manganese (Mn) |
0.25−0.55 |
Copper (Cu), no more |
0.30 |
Nickel (Ni) |
4.00−4.40 |
Sulfur (S), no more |
0.025 |
Carbon (C) |
0.14−0.20 |
Phosphorus (P), no more |
0.025 |
Chromium (Cr) |
1.35−1.65 |
Mechanical properties of steel 18Х2Н4ВА
Heat treatment, delivery condition |
Section, mm |
σ 0.2, MPa |
σ B, MPa |
δ 5 ,% |
ψ,% |
KCU, J / m 2 |
HB |
Bar. Hardening 950 ° C, air. Hardening 860 ° C, air. Vacation: 200 ° C, air or oil |
|
fifteen |
835 |
1130 |
12 |
50 |
98 |
|
Bar. Hardening 950 ° C, air. Hardening 860 ° C, air. Vacation: 550 ° C, air or oil |
|
fifteen |
785 |
1030 |
12 |
50 |
118 |
|
Forgings. Hardening. Vacation. |
KP 685 |
300−500 |
685 |
835 |
eleven |
33 |
39 |
262−311 |
KP 735 |
100−300 |
735 |
880 |
12 |
35 |
49 |
277−321 |
KP 785 |
<100 |
785 |
930 |
12 |
40 |
59 |
293−331 |
Annealing 890−910 ° С, cooling with a furnace |
|
300 |
390 |
620 |
ten |
25 |
|
265 |
Normalization 920−980 ° C, air. Vacation 630−680 ° С, air. |
|
|
590 |
780 |
|
60 |
|
197−269 |
Cementation 920−950 ° C. Normalization 900−950 ° C, air. Hardening 900−950 ° С, oil. Vacation (double) 630−650 ° С, air. |
|
80 |
1270 |
1370 |
12 |
|
88 |
321−400 |
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 |
20 |
1090 |
1240 |
12 |
61 |
127 |
200 |
1060 |
1190 |
12 |
60 |
137 |
300 |
1050 |
1200 |
114 |
64 |
118 |
400 |
960 |
1060 |
fourteen |
69 |
108 |
500 |
810 |
880 |
fourteen |
70 |
98 |
550 |
710 |
750 |
sixteen |
73 |
108 |
Sample 6 mm in diameter, 30 mm long, rolled. Deformation rate 16 mm / min. Strain rate 0.009 1 / s. |
700 |
225 |
265 |
31 |
69 |
|
800 |
73 |
130 |
35 |
34 |
|
900 |
55 |
79 |
22 |
23 |
|
1000 |
41 |
55 |
31 |
36 |
|
1100 |
24 |
36 |
63 |
100 |
|
1200 |
20 |
25 |
46 |
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 |
Hardening 850 ° С, oil. |
200 |
1170 |
1470 |
12 |
64 |
114 |
300 |
1140 |
1390 |
12 |
64 |
98 |
400 |
1040 |
1280 |
12 |
63 |
86 |
500 |
950 |
1180 |
thirteen |
66 |
92 |
600 |
710 |
940 |
19 |
73 |
183 |
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 |
HRC e |
Hardening 860 ° C, oil. Vacation 200 ° С |
Sample cutting location — center |
40 |
1070 |
1300 |
fourteen |
69 |
150 |
43 |
Sample cutting location — center |
60 |
1110 |
1250 |
fifteen |
62 |
140 |
41 |
Sample cutting place — 1 / 2R |
80 |
1130 |
1250 |
12 |
54 |
170 |
42 |
Sample cutting place — 1 / 2R |
100 |
1100 |
1230 |
fifteen |
63 |
160 |
40 |
Sample cutting location — 1 / 3R |
120 |
1090 |
1220 |
thirteen |
60 |
160 |
41 |
Hardening 860 ° C, water. Vacation 200 ° С |
Sample cutting location — center |
40 |
1220 |
1420 |
thirteen |
66 |
110 |
45 |
Sample cutting location — center |
60 |
1280 |
1420 |
thirteen |
61 |
120 |
45 |
Sample cutting place — 1 / 2R |
80 |
1250 |
1390 |
12 |
45 |
150 |
45 |
Sample cutting place — 1 / 2R |
100 |
1210 |
1360 |
thirteen |
57 |
130 |
44 |
Sample cutting location — 1 / 3R |
120 |
1240 |
1340 |
12 |
42 |
140 |
41 |
Technological properties of steel 18Kh2N4VA
Forging temperature |
The beginning is 1200, the end is 800. Slow cooling up to 150 C followed by high vacation no later than 4−6 hours. |
Weldability |
difficult to weld. Welding methods: RDS, ADS submerged arc, EShS. Heating and subsequent heat treatment are required. |
Machinability by cutting |
at HB 156−207 K υ tv.spl. = 0.8, K υ b.st. = 0.7. |
Tendency to release ability |
not inclined |
Flock sensitivity |
sensitive |
Temperature of critical points of steel 18Х2Н4ВА
Critical point |
° C |
Ac1 |
700 |
Ac3 |
810 |
Ar3 |
400 |
Ar1 |
350 |
Mn |
336 |
Endurance limit of steel 18Kh2N4VA
σ -1, MPa |
τ -1, MPa |
n |
σ B, MPa |
σ 0.2, MPa |
Heat treatment, steel condition |
540 |
|
5E + 6 |
1360 |
|
Hardening 850 С, oil. Vacation 180 C. |
475 |
|
5E + 6 |
1220 |
|
Hardening 850 С, oil. Vacation 400 S. |
540 |
228 |
5E + 6 |
1270 |
|
|
470 |
226 |
5E + 6 |
910 |
|
|
696 |
|
|
1230 |
1110 |
HB 383 |
774 |
|
|
1300 |
1180 |
HB 404 |
Hardenability of steel 18Х2Н4ВА
Distance from the end, mm / HRC e |
1.5 |
nine |
eleven |
fifteen |
20 |
25 |
thirty |
40 |
50 |
40.5−48.5 |
40.5−48.5 |
39.5−47.5 |
39.5−47.5 |
38.5−46.5 |
37.5−46.5 |
36.5−45.5 |
35−45.5 |
32−44.5 |
Physical properties of steel 18Х2Н4ВА
Test temperature, ° С |
20 |
100 |
200 |
300 |
400 |
500 |
600 |
700 |
800 |
900 |
Normal elastic modulus, E, GPa |
200 |
165 |
141 |
|
139 |
|
|
|
|
|
Density of steel, pn, kg / m 3 |
7950 |
7930 |
7900 |
7860 |
7830 |
7800 |
7760 |
|
|
|
Thermal conductivity coefficient W / (m ° С) |
|
36 |
36 |
35 |
35 |
34 |
33 |
32 |
thirty |
|
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) |
11.7 |
12.2 |
12.7 |
13.1 |
13.5 |
13.9 |
|
|
|
|