50KHN steel is used: for the manufacture of rolls for hot rolling, the shaft-gears, gear wheels, tires, crankshafts, connecting rods, bolts, exhaust valves and other major performance parts; forgings, rolls for hot rolling and cold rolling of metals without mechanical processing.

Note

Structural steel high-quality stainless.

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 10702-78, GOST 14955-77, TU 14-1-2118-77, TU 14-11-245-88, TU 14-1-5228-93, 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
Blanks. Of the workpiece. Slabs	В31	OST 3-1686-90, TU 14-1-4944-90
Processing of metals by pressure. Forgings	В03	TU 108-11-905-87

Chemical composition

Standard	C	S	P	Mn	Cr	Si	Ni	Fe	Cu	V	Ti	Mo	W
GOST 4543-71	0.46-0.54	≤0.035	≤0.035	0.5-0.8	0.45-0.75	0.17-0.37	1-1.4	Rest	≤0.3	≤0.05	≤0.03	≤0.15	≤0.2

Fe is the basis.
According to GOST 4543-71 the content in high-quality steel is regulated: P≤0,025%; S≤0.025%; Сu≤0.30%; in high-grade steel: P≤0,025%; S≤0.015%; Сu≤0.25%.

Mechanical properties

Section, mm	t отпуска, °C	s_T\|s_0,2, MPa	σ_U, MPa	d₅, %	y, %	KCU, kJ/m²	HB, MPa	HRC
Hot-rolled steel and hot rolled with special surface finish
-	-	-	-	-	-	-	≤197	-
Steel calibrated and calibrated with special surface finish
-	-	-	-	-	-	-	≤217	-
Quenching in water or oil from 820 °C to + leave at 530 °C, cooling in water or oil
≤25	-	885	1080	9	40	481	-	-
Normalization at 840-870 °C, air cooling + vacation at 580-630 °C, cooling with the furnace
100-300	-	450	760	12	35	285	229-285	-
Heating up to 1200 °C, exposure time 10 h, forging, isothermal annealing, normalization, high holiday
960	-	380	770	18	37	343	-	-
Quenching in oil from 800 °C + vacation
-	200	1520	1760	8	25	-	460	-
Quenching in oil from 840 °C to + vacation at 480 °C
-	-	720	910	21	-	-	-	-
Quenching in oil with 810-830 °C + vacation at 180-220 °C, air cooling
25-40	-	1470	1670	8	25	383	-	50-55
Normalization at 840-870 °C, air cooling + vacation at 580-630 °C, cooling with the furnace
301-600	-	420	730	12	30	245	223-269	-
Heating up to 1200 °C, exposure time 10 h, forging, isothermal annealing, normalization, high holiday
960	-	330	720	10	9	196	-	-
Quenching in oil from 800 °C + vacation
-	300	1420	1640	7	32	-	445	-
Quenching in oil from 840 °C to + vacation at 480 °C
-	-	680	880	-	-	-	-	-
Quenching in oil from 820 °C to + leave at 500 °C, cooling in water or oil
40-60	-	780	980	9	40	481	269	-
Normalization at 840-870 °C, air cooling + vacation at 580-630 °C, cooling with the furnace
601-900	-	390	690	11	25	-	207-255	-
Quenching in oil from 800 °C + vacation
-	400	1220	1420	11	41	-	385	-
Quenching in oil from 840 °C to + vacation at 480 °C
-	-	670	-	27	-	-	-	-
Quenching in oil from 820-840 °C + vacation at 550-600 °C, cooling in water or oil
60-120	-	640	780	-	-	579	250-285	-
Normalization at 840-870 °C, air cooling + vacation at 580-630 °C, cooling with the furnace
901-1200	-	340	670	10	20	-	201-241	-
Quenching in oil from 800 °C + vacation
-	500	980	1160	14	52	-	310	-
Quenching in oil from 840 °C to + vacation at 480 °C
-	-	520	670	25	-	-	-	-
Quenching in oil from 800 °C + vacation
-	600	740	930	20	60	-	250	-

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	r, kg/m³	l, W/(m · °C)	a, 10^-6 1/°C	С, J/(kg · °C)
0	7860	-	-	-
20	7860	-	-	-
100	-	43	118	500
200	-	40	118	510
300	-	39	123	560
400	-	38	134	630
500	-	37	134	700
600	-	36	-	800
700	-	32	14	910
800	-	23	-	650
900	-	24	-	610
1000	-	-	-	610
1200	-	-	-	700

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	not applicable for welded structures (except CCC).
Склонность к отпускной хрупкости	inclined
The temperature of forging	Start - 1200 °C, the end - of 800 °C. the cross Sections up to 250 mm are cooled in air, 251-350 mm - in the pit.
Flock-sensitive sensitivity	sensitive
Machinability	In the normalized and tempered condition with a HB 170-217 Kn TV.SPL.=0.7 Kn b.St.=0.8

Steel 50KHN

Designation

Description