Steel 38KHN3MFA (38ХН3МФ)

Designation

Name	The value
Designation GOST Cyrillic	38ХН3МФА
Designation GOST Latin	38XH3MFA
Transliteration	38HN3MFA
By chemical elements	38CrН3MoV

Name	The value
Designation GOST Cyrillic	38ХН3МФ
Designation GOST Latin	38XH3MF
Transliteration	38HN3MF
By chemical elements	38CrН3MoV

Description

38KHN3MFA steel is used: for the production of rings of turbogenerators and most critical highly loaded parts operating at temperatures up to +400 °C; heavily loaded parts of pipe fittings; forged billets for rotors of troubleproof; billet forged shafts and rotors, stationary and transport steam turbines.

Note

Structural steel high-quality hromonikelemolibdenovyh.

Standards

Name	Code	Standards
Sheets and strips	В23	GOST 103-2006
Bars and shapes	В32	GOST 1051-73, GOST 4543-71, GOST 7417-75, GOST 8559-75, GOST 8560-78, GOST 14955-77, TU 14-1-2118-77, TU 14-11-245-88, TU 14-1-1271-75, TU 14-136-367-2008
Bars and shapes	В22	GOST 1133-71, GOST 8319.0-75, GOST 2590-2006, GOST 2591-2006, GOST 2879-2006
Processing of metals by pressure. Forgings	В03	GOST 8479-70, OST 5Р.9125-84, OST 26-01-135-81, TU 3-896-78, TU 108-1029-81, TU 108-11-910-87, TU 108-11-921-87, ST ЦКБА 010-2004, TU 108-11-342-87
Blanks. Of the workpiece. Slabs	В31	OST 3-1686-90, TU 108-11-440-87, TU 108.11.889-87, TU 14-1-1937-77, TU 14-1-4944-90, TU 14-1-4797-90
Thermal and thermochemical treatment of metals	В04	ST ЦКБА 026-2005
Sheets and strips	В33	TU 14-1-5036-91
Steel cylinders	В66	TU 14-159-257-98, TU 14-3-644-77

Chemical composition

Standard	C	S	P	Mn	Cr	Si	Ni	Fe	Cu	V	Ti	Mo	W
TU 108-1029-81	0.34-0.42	≤0.022	≤0.025	0.25-0.55	1.2-1.5	≤0.37	3-3.4	Rest	≤0.25	0.1-0.2	-	0.35-0.45	-
GOST 4543-71	0.33-0.4	≤0.025	≤0.025	0.25-0.5	1.2-1.5	0.17-0.37	3-3.5	Rest	≤0.3	0.1-0.18	≤0.03	0.35-0.45	≤0.2

Fe is the basis.
GOST 4543-71 regulates the content of high-quality steel: P≤0,025%; S≤0.015%; Сu≤0.25%.
According to TU 108.11.889-87, deviations in chemical composition are allowed: by carbon ± 0.010%, by chroma ± 0.050%, by manganese ± 0.020%, by molybdenum ± 0.020%, by vanadium ± 0.020%, by nickel -0.10% , for silicon +0.020%. The total content of sulfur and phosphorus should not be more than 0.036% for smelting by a duplex process and in an electric furnace. The sulfur and phosphorus content after the use of the out-of-furnace refining and evacuation unit (OVPV) should not be more than 0.010% and 0.012%, respectively, for a sum of sulfur and phosphorus not more than 0.020%. The steel shall be melted according to the manufacturer's technical documentation using the UVRB unit. It is allowed to melt steel in an open-hearth furnace by a duplex process or in the main electric arc furnace.
According to TU 108-1029-81 the chemical composition is given for steel grade 38HN3MFA. In the workpieces, deviations in the content of the elements indicated in the table are allowed: carbon ± 0.010%, silicon + 0.030%. For metal VDP, the deviation of manganese content +0.10% / - 0.15% is allowed. The deviation of the silicon content in the metal VDP and ESR is allowed within ± 0.050%. In the ESR steel, the sulfur content should not be more than 0.015%. The total content of sulfur and phosphorus should not be more than 0.040%.

Mechanical properties

Section, mm	t отпуска, °C	s_T\|s_0,2, MPa	σ_U, MPa	d₅, %	y, %	KCU, kJ/m²	HB, MPa	HRC
Quenching in oil from 850 °C + vacation
-	200	1590	1800	11	43	589	-	52
-	300	1470	1080	9	46	490	-	48
-	400	1400	150	10	45	471	-	46
-	500	1290	1370	11	45	579	-	44
-	600	1130	1200	14	55	540	-	39
Quenching in oil from 850 °C + vacation at 560 °C, air cooling (named place of clippings sample)
160-200	-	1210	1260	12	49	687	-	-
Quenching + tempering (forgings)
500-800	-	640	785	10	30	383	248-293	-
Billet shafts and rotors of steam turbines on the other 108-1029-81 (in the delivery condition specified strength and direction and place the cuttings sample)
-	-	638-834	≥804	≥14	≥40	≥590	-	-
Forged billet rings for turbine generators of thermal power plants up to 500 MW I-VIII categories THAT 3-896-78 (samples tangential)
-	-	294	491	16	30	294	-	-
Quenching in oil from 850 °C + vacation at 560 °C, air cooling (named place of clippings sample)
≤30	-	1250	1330	13	52	687	-	-
Quenching + tempering (forgings)
500-800	-	685	835	10	30	383	262-311	-
Billet shafts and rotors of steam turbines on the other 108-1029-81 (in the delivery condition specified strength and direction and place the cuttings sample)
-	-	638-834	≥765	≥11	≥32	≥440	-	-
Forged billet rings for turbine generators of thermal power plants up to 500 MW I-VIII categories THAT 3-896-78 (samples tangential)
-	-	392	589	16	30	491	-	-
Quenching in oil from 850 °C + vacation at 560 °C, air cooling (named place of clippings sample)
160-200	-	1070	1150	13	40	785	-	-
Quenching + tempering (forgings)
500-800	-	735	880	-	-	-	277-321	-
Billet shafts and rotors of steam turbines on the other 108-1029-81 (in the delivery condition specified strength and direction and place the cuttings sample)
-	-	667-834	≥834	≥14	≥40	≥590	-	-
Forged billet rings for turbine generators of thermal power plants up to 500 MW I-VIII categories THAT 3-896-78 (samples tangential)
-	-	491	687	16	30	392	-	-
Quenching in oil from 850 °C + vacation at 560 °C, air cooling (named place of clippings sample)
30-50	-	1210	1300	13	52	716	-	-
Quenching + tempering (forgings)
100-300	-	785	930	11	35	481	293-331	-
Billet shafts and rotors of steam turbines on the other 108-1029-81 (in the delivery condition specified strength and direction and place the cuttings sample)
-	-	667-834	≥834	≥10	≥30	≥390	-	-
Forged billet rings for turbine generators of thermal power plants up to 500 MW I-VIII categories THAT 3-896-78 (samples tangential)
-	-	589	765	16	35	491	-	-
Quenching in oil (or water in oil) from 840-860 °C (exposure for 2.5-4.5 hours depending on the thickness and weight of the workpiece) with the following tempering in oil or air
≤100	570-580	980-1078	1176	7	35	490	-	39.6-43.5
Quenching using water in oil from 850 °C + vacation at 600 °C, air cooling (named place of clippings sample)
120-160	-	1160	1220	15	54	736	-	-
Quenching + tempering (forgings)
300-500	-	785	930	10	30	383	293-331	-
Forged billet rings for turbine generators of thermal power plants up to 500 MW I-VIII categories THAT 3-896-78 (samples tangential)
-	-	687	834	14	35	491	-	-
Quenching in oil (or water in oil) from 840-860 °C (exposure for 2.5-4.5 hours depending on the thickness and weight of the workpiece) with the following tempering in oil or air
≤150	580-590	880-980	1078	10	35	490	-	34.8-42.5
Quenching using water in oil from 850 °C + vacation at 600 °C, air cooling (named place of clippings sample)
200-240	-	1170	1210	14	53	765	-	-
Normalization (forgings)
100-300	-	685	835	12	38	481	262-311	-
Forged billet rings for turbine generators of thermal power plants up to 500 MW I-VIII categories THAT 3-896-78 (samples tangential)
-	-	785	932	13	35	392	-	-
Quenching in oil (or water in oil) from 840-860 °C (exposure for 2.5-4.5 hours depending on the thickness and weight of the workpiece) with the following tempering in oil or air
≤240	590-600	785-880	980	10	38	490	-	30.9-38.6
Quenching using water in oil from 850 °C + vacation at 600 °C, air cooling (named place of clippings sample)
120-160	-	1150	1200	13	40	863	-	-
Normalization (forgings)
300-500	-	685	835	11	33	383	262-311	-
Forged billet rings for turbine generators of thermal power plants up to 500 MW I-VIII categories THAT 3-896-78 (samples tangential)
-	-	883	1010	12	30	392	-	-
Quenching in oil (or water in oil) from 840-860 °C (exposure for 2.5-4.5 hours depending on the thickness and weight of the workpiece) with the following tempering in oil or air
≤350	600-620	675-785	882	10	40	588	-	28-38.6
Quenching using water in oil from 850 °C + vacation at 600 °C, air cooling (named place of clippings sample)
200-240	-	1070	1130	13	50	834	-	-
Normalization (forgings)
100-300	-	735	880	12	35	481	277-321	-
Forged billet rings for turbine generators of thermal power plants up to 500 MW I-VIII categories THAT 3-896-78 (samples tangential)
-	-	981	1079	11	30	294	-	-
Quenching in oil (or water in oil) from 840-860 °C (exposure for 2.5-4.5 hours depending on the thickness and weight of the workpiece) with the following tempering in oil or air
≤30	550-570	1176-1274	1372	7	35	392	-	42.5-46.4
Quenching using water in oil from 850 °C + vacation at 600 °C, air cooling (named place of clippings sample)
50-80	-	1130	1190	14	52	824	-	-
Normalization (forgings)
≤100	-	785	930	12	40	579	293-331	-
Quenching in oil from 850 °C + vacation at 600 °C, air cooling
25	-	1080	1180	12	50	765	-	-
Quenching using water in oil from 850 °C + vacation at 600 °C, air cooling (named place of clippings sample)
80-120	-	1110	1170	14	52	912	-	-

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
HRC	Rockwell hardness (indenter diamond spheroconical)

Physical characteristics

Temperature	Е, HPa	G, HPa	r, kg/m³	l, W/(m · °C)	R, Mr. · m	a, 10^-6 1/°C	С, J/(kg · °C)
0	210	83	7900	34	300	-	-
20	210	-	7900	34	300	-	-
100	203	80	-	34	321	12	496
200	197	77	-	34	365	125	508
300	190	75	-	33	437	129	525
400	184	72	-	32	516	133	538
500	176	69	-	32	613	136	567
600	170	66	-	30	750	138	601
700	154	60	-	29	897	138	672
800	137	53	-	28	1080	138	672
1000	-	-	-	-	-	107	697

A description of the physical symbols

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

Technological properties

Name	The value
Weldability	Does not apply to welded structures.
Склонность к отпускной хрупкости	Tend not.
The temperature of forging	Start - 1180 °C, the end - 780 °C. the cross Sections up to 100 mm was cooled in the pit, over 100 mm are subjected to low temperature annealing.
Flock-sensitive sensitivity	Excessively sensitive.