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	s_T\|s_0,2, MPa	σ_U, 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
s_T\|s_0,2	Yield strength or limit of proportionality with a tolerance for residual deformation of 0.2%
σ_U	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.