50X steel is used: for the production of shafts, spindles, screws, large gear wheels, gear shafts, thrust washers, rolls for hot rolling and other upgradable parts, which are requirements of high hardness, wear resistance, strength, running minor impact loads.

Note

Structural steel high-quality chrome.

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 14-136-367-2008
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, ST ЦКБА 010-2004
Blanks. Of the workpiece. Slabs	В31	OST 3-1686-90, TU 14-1-4944-90

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	0.8-1.1	0.17-0.37	≤0.3	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, %	d₁₀	y, %	KCU, kJ/m²	HB, MPa	HRC
Quenching in oil from 820 °C to + vacation at 650 °C
≤25	-	760	980	10	-	45	590	-	-
Hardening + Vacation
500-800	-	345	590	12	-	38	390	174-217	-
A rod with a diameter of 25 mm. Quenching in oil from 820 °C [118]
-	300	1670	1810	10	-	30	-	520	-
Sample diameter 10 mm, length 100 mm Quenching in oil from 820-840 °C + vacation at 600-650 °C, air cooling
-	-	-	87	-	21	37	-	-	-
Hardened in oil from 830 °C to + vacation at 190 °C
≤25	-	1270	1470	6	-	22	290	-	46
Hardening + Vacation
100-300	-	540	685	13	-	40	490	223-262	-
A rod with a diameter of 25 mm. Quenching in oil from 820 °C [118]
-	400	1520	1670	13	-	40	-	470	-
Sample diameter 10 mm, length 100 mm Quenching in oil from 820-840 °C + vacation at 600-650 °C, air cooling
-	-	-	43	-	14	23	-	-	-
Hardened in oil from 830 °C to + vacation at 520 °C, cooling in water
≤25	-	885	1080	9	-	40	390	-	-
Hardening + Vacation
100-300	-	590	735	13	-	40	490	235-277	-
A rod with a diameter of 25 mm. Quenching in oil from 820 °C [118]
-	500	1270	1420	17	-	52	-	400	-
Sample diameter 10 mm, length 100 mm Quenching in oil from 820-840 °C + vacation at 600-650 °C, air cooling
-	-	-	25	-	16	20	-	-	-
Hardening + Vacation
≤100	-	640	785	13	-	42	590	248-293	-
A rod with a diameter of 25 mm. Quenching in oil from 820 °C [118]
-	600	1030	1180	21	-	60	-	320	-
Sample diameter 10 mm, length 100 mm Quenching in oil from 820-840 °C + vacation at 600-650 °C, air cooling
-	-	-	21	-	35	61	-	-	-
Normalization
≤100	-	345	590	18	-	45	590	174-217	-
A rod with a diameter of 50 mm. Quenching in oil from 820 °C to + vacation, cooling in oil [84]
-	400	1520	1620	-	4	39	49	-	-
Normalization
100-300	-	345	590	17	-	40	540	174-217	-
A rod with a diameter of 50 mm. Quenching in oil from 820 °C to + vacation, cooling in oil [84]
-	500	1180	1270	-	9	50	147	-	-
Normalization
300-500	-	345	590	14	-	38	490	174-217	-
A rod with a diameter of 50 mm. Quenching in oil from 820 °C to + vacation, cooling in oil [84]
-	600	540	850	-	17	61	-	-	-

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
d₁₀	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	a, 10^-6 1/°C
0	207	78	7820	-
20	207	-	7820	-
100	-	-	-	128
200	-	-	-	13
300	-	-	-	13
500	-	-	-	138

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	difficult weldability. Welding methods: RDS - necessary heating and subsequent heat treatment. CCC - a necessary subsequent heat treatment.
Склонность к отпускной хрупкости	inclined
The temperature of forging	Start - 1250 °C, the end - 770 °C. the cross Sections up to 100 mm are cooled in air, section 101-300 mm - mulde.
Flock-sensitive sensitivity	sensitive
Machinability	In hot-rolled state when HB 207 and blower SB=630 MPa Kn TV.SPL.=0.85 Kn b.St.=0.80

Steel 50S

Designation

Description