20KHGNR steel is used: for the manufacture of gear wheels, shaft-gear, worm, Cam couplings, bushings and other critical parts operating under conditions of shock loads.

Note

Structural steel quality homomorphically with titanium and boron.

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
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	B	Ti
GOST 4543-71	0.16-0.23	≤0.035	≤0.035	0.7-1	0.7-1.1	0.17-0.37	0.8-1.1	Rest	≤0.3	≤0.05	0.001-0.005	≤0.06

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
Normalization of 930°C, air Annealing of 840°C, oil, Vacation, 200°C, air.
15-25	-	1370	1420	14	60	1060	-	-
Bars. Normalizing at 930 °C, air cooling + tempering in oil from 840 °C to + vacation at 200 °C, air cooling
100-150	-	830	1000	16	50	961	286	-
When carburizing 930-950 °C + quenching in oil 830-850 °C + vacation at 170-230 °C, air cooling
≤15	-	1360	1460	13	60	1158	-	57-63
Quenching in oil from 860 °C to + leave + cooling in oil
-	200	1250	1510	11	55	598	-	47
A sample with diameter 10 mm, length 50 mm, laminated. The rate of deformation of 20 mm/min strain Rate 0,007 1/s.
-	-	115	12	41	84	-	-	-
Normalization of 930°C, air Annealing of 840°C, oil, Vacation, 200°C, air.
25-50	-	1110	1200	12	62	1442	-	-
Bars. Normalizing at 930 °C, air cooling + tempering in oil from 840 °C to + vacation at 200 °C, air cooling
15-25	-	1370	1420	14	60	1060	418	-
When carburizing 930-950 °C + quenching in oil 830-850 °C + vacation at 170-230 °C, air cooling
100-150	-	880	1040	17	50	1060	286	57-63
Quenching in oil from 860 °C to + leave + cooling in oil
-	300	1230	1400	8	50	608	-	47
A sample with diameter 10 mm, length 50 mm, laminated. The rate of deformation of 20 mm/min strain Rate 0,007 1/s.
-	-	73	81	47	100	-	-	-
Normalizing at 930-950 °C, air cooling + tempering in oil with 780-830 °C + vacation at 200 °C, cooling in air or in oil
≤15	-	1080	1270	10	50	863	-	-
Bars. Normalizing at 930 °C, air cooling + tempering in oil from 840 °C to + vacation at 200 °C, air cooling
25-50	-	1110	1200	12	62	1442	340	-
When carburizing 930-950 °C + quenching in oil 830-850 °C + vacation at 170-230 °C, air cooling
15-25	-	1310	1410	14	64	1246	-	57-63
Quenching in oil from 860 °C to + leave + cooling in oil
-	400	1180	1240	11	58	677	-	43
A sample with diameter 10 mm, length 50 mm, laminated. The rate of deformation of 20 mm/min strain Rate 0,007 1/s.
-	-	32	44	58	100	-	-	-
Bars. Normalizing at 930 °C, air cooling + tempering in oil from 840 °C to + vacation at 200 °C, air cooling
50-75	-	970	1060	15	60	1060	302	-
When carburizing 930-950 °C + quenching in oil 830-850 °C + vacation at 170-230 °C, air cooling
25-50	-	1160	1260	13	64	1246	340	57-63
Quenching in oil from 860 °C to + leave + cooling in oil
-	500	970	970	14	64	1226	-	33
A sample with diameter 10 mm, length 50 mm, laminated. The rate of deformation of 20 mm/min strain Rate 0,007 1/s.
-	-	19	29	63	100	-	-	-
Bars. Normalizing at 930 °C, air cooling + tempering in oil from 840 °C to + vacation at 200 °C, air cooling
75-100	-	920	1000	15	60	1246	302	-
When carburizing 930-950 °C + quenching in oil 830-850 °C + vacation at 170-230 °C, air cooling
50-75	-	1080	1140	12	60	1246	321	57-63
Quenching in oil from 860 °C to + leave + cooling in oil
-	600	690	820	17	65	1785	-	27
A sample with diameter 10 mm, length 50 mm, laminated. The rate of deformation of 20 mm/min strain Rate 0,007 1/s.
-	-	15	25	76	100	-	-	-
When carburizing 930-950 °C + quenching in oil 830-850 °C + vacation at 170-230 °C, air cooling
75-100	-	930	1040	17	66	1246	302	57-63

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)

Technological properties

Name	The value
Weldability	RDS. Recommended heating and subsequent heat treatment.
The tendency to temper brittleness	inclined
The temperature of forging	Start - 1150 °C, the end - of 800 °C. Sections longer than 60 mm are cooled slowly.
Flock-sensitive sensitivity	sensitive