Steel 15KH12VNMF (ЭИ802)

Designation

Name The value
Designation GOST Cyrillic 15Х12ВНМФ
Designation GOST Latin 15X12BHMF
Transliteration 15H12VNMF
By chemical elements 15Cr12WНMoV
Name The value
Designation GOST Cyrillic ЭИ802
Designation GOST Latin EI802
Transliteration EhI802
By chemical elements -

Description

15KH12VNMF steel is used: for the manufacture of steam turbine blades operating at temperatures up to +580 °C; rotors, disks, blades, bolts, bands, nuts, pins and other parts operating at temperatures up to +780 °C.

Note

Steel high-temperature martensite-ferritic class.
The recommended maximum operating temperature for a long time — up to 780 °C. the Temperature of beginning of intensive scaling in air +950 °C.

Standards

Name Code Standards
Sheets and strips В23 GOST 103-2006
Bars and shapes В22 GOST 1133-71, GOST 2590-2006, GOST 2591-2006, GOST 2879-2006
Sheets and strips В33 GOST 4405-75
Classification, nomenclature and General rules В30 GOST 5632-72
Bars and shapes В32 GOST 5949-75, GOST 7417-75, GOST 8559-75, GOST 8560-78, GOST 14955-77, GOST 18968-73, GOST 19442-74, TU 14-11-245-88
Blanks. Of the workpiece. Slabs В31 OST 108.020.03-82, OST 3-1686-90

Chemical composition

Standard C S P Mn Cr Si Ni Fe Cu V Ti Mo W
GOST 5632-72 0.12-0.18 ≤0.025 ≤0.03 0.5-0.9 11-13 ≤0.4 0.4-0.8 Rest ≤0.3 0.15-0.3 ≤0.2 0.5-0.7 0.7-1.1
Fe is the basis.

Mechanical properties

Section, mm sT|s0,2, MPa σU, MPa d5, % y, % KCU, kJ/m2 HB, MPa
Bars and strip hot rolled and forged GOST 18968-73. Normalization or quenching at 1010-1060 °C, cooling in oil + Leave in 660-770 °C, air cooling
590-735 ≥740 ≥15 ≥50 ≥588 229-269
Disc diameter 750-1020 mm, height 300 mm. Forging rotor diameter 1140 mm. Quenching in oil from 1050 °C to + Vacation at 720 °C (sample tangential). At 20 °C NV=228-248
- 600-650 750-810 14-23 41-55 - -
Disk with a diameter of 700 mm, a height of 300 mm (indicated temperature and time of heat exposure)
- ≥600 ≥790 ≥21 ≥57 - ≥241
Bars hot rolled and forged according to GOST 5949-75. Annealing at 900-950 °C, cooling in furnace + Quenching in oil from 1000-1020 °C + Vacation at 600-700 °C, air cooling
≥590 ≥740 ≥15 ≥45 ≥588 -
Disc diameter 750-1020 mm, height 300 mm. Forging rotor diameter 1140 mm. Quenching in oil from 1050 °C to + Vacation at 720 °C (sample tangential). At 20 °C NV=228-248
- 580-610 720-760 16-18 45-53 - -
Disk with a diameter of 700 mm, a height of 300 mm (indicated temperature and time of heat exposure)
- ≥580 ≥750 ≥21 ≥49 - ≥241
Rolled steel. Quenching in oil from 1050 °C + Vacation at 740 °C, air cooling
≤60 ≥510 ≥690 ≥18 ≥57 ≥686 -
Disc diameter 750-1020 mm, height 300 mm. Forging rotor diameter 1140 mm. Quenching in oil from 1050 °C to + Vacation at 720 °C (sample tangential). At 20 °C NV=228-248
- 540-570 690-710 13-17 37-54 - -
The forging of a rotor with a diameter of 1000 mm (provided the temperature and time of heat exposure)
- ≥660 ≥810 ≥17 ≥44 - ≥262
Contoured rods (g/K, x/K and x/t for steam turbine blades; x/a and x/t for coupling blades of steam turbines) according to GOST 19442-74. Quenching in oil with 1010-1060 °C to + Leave in 660-770 °C, air cooling (specified strength)
588-735 735-931 ≥15 ≥50 ≥588 229-269
Disc diameter 750-1020 mm, height 300 mm. Forging rotor diameter 1140 mm. Quenching in oil from 1050 °C to + Vacation at 720 °C (sample tangential). At 20 °C NV=228-248
- 520-540 640-680 13-17 46-51 - -
The forging of a rotor with a diameter of 1000 mm (provided the temperature and time of heat exposure)
- ≥630 ≥780 ≥14 ≥42 - ≥255
Disc diameter 750-1020 mm, height 300 mm. Forging rotor diameter 1140 mm. Quenching in oil from 1050 °C to + Vacation at 720 °C (sample tangential). At 20 °C NV=228-248
- 500-510 610-630 - 45-51 - -
The forging of a rotor with a diameter of 1000 mm (provided the temperature and time of heat exposure)
- ≥480 ≥660 ≥21 ≥40 - ≥207
Disc diameter 750-1020 mm, height 300 mm. Forging rotor diameter 1140 mm. Quenching in oil from 1050 °C to + Vacation at 720 °C (sample tangential). At 20 °C NV=228-248
- 440-460 510-530 15-19 52-61 - -
The forging of a rotor with a diameter of 1000 mm (provided the temperature and time of heat exposure)
- ≥440 ≥630 ≥26 ≥51 - ≥196
Disc diameter 750-1020 mm, height 300 mm. Forging rotor diameter 1140 mm. Quenching in oil from 1050 °C to + Vacation at 720 °C (sample tangential). At 20 °C NV=228-248
- 330-350 340-360 21-31 83-85 - -
Bars with a diameter of 40-120 mm. Quenching in oil from 1050 °C to + Vacation at 700 °C. At 20 °C NV=255-271
- 700-730 830-870 15-18 55-59 - -
- 600-620 720-730 14-15 59-63 - -
- 570-590 670-680 13-14 55-62 - -
- 520-570 550-570 14-15 59-78 - -
- 455-470 500-520 18-19 78-79 - -
- 350-370 370-395 20-23 79-88 - -
- 275-315 295-340 26 87 - -

Description mechanical marks

Name Description
sT|s0,2 Yield strength or limit of proportionality with a tolerance for residual deformation of 0.2%
σU Limit short-term strength
d5 Elongation after rupture
y The relative narrowing
KCU Toughness
HB Brinell hardness number

Physical characteristics

Temperature Е, HPa r, kg/m3 l, W/(m · °C) a, 10-6 1/°C С, J/(kg · °C)
0 212 7850 - - -
20 216 7850 - - -
100 207 7830 25 105 477
200 202 7800 25 108 498
300 196 7780 26 111 545
400 190 7760 26 114 625
500 181 7730 27 116 741
600 167 7700 27 118 896
700 - 7670 272 119 -
800 - - 276 12 -
1000 - - - 107 -
1200 - - - 116 -

A description of the physical symbols

Name Description
Е The normal elasticity modulus
r Density
l Coefficient of thermal conductivity
R UD. the resistivity

Technological properties

Name The value
Weldability difficult weldability. For welding use electrode KTN-10, to welding full heat treatment after welding - vacation at 700 °C for 5 h or at 680 °C for 10 h, cooling with the furnace.
The temperature of forging Start - 1230 °C, the end of - 900 °C. the cross Sections up to 250 mm is subjected to annealing, one hypothermia. Sections from 250 to 400 mm - annealing and two hypothermia.
Machinability when HB 230 Kn TV.SPL.=1.1 Kn b.St.=0.5.