40KHN steel is used: for the production of forgings and stampings, axles, shafts, connecting rods, gear wheels, shafts, excavators, couplings, shaft gear, spindles, bolts, levers, rods, cylinders and other critical loaded parts subjected to vibration and dynamic loads, which are requirements of high strength and toughness; rail and structural steel mill rolls and heavy section mill for hot rolling metal.

Note

Structural steel high-quality stainless.

Standards

Name	Code	Standards
Sheets and strips	В23	GOST 103-2006
Bars and shapes	В22	GOST 1133-71, GOST 8319.0-75, GOST 2590-2006, GOST 2591-2006, GOST 2879-2006
Bars and shapes	В32	GOST 4543-71, GOST 7417-75, GOST 8560-78, GOST 10702-78, GOST 14955-77, TU 108.11-927-87, TU 14-1-2118-77, TU 14-11-245-88, TU 14-1-1271-75, TU 14-1-5228-93, TU 14-136-367-2008
Processing of metals by pressure. Forgings	В03	GOST 8479-70, OST 5Р.9125-84, ST ЦКБА 010-2004
Blanks. Of the workpiece. Slabs	В31	OST 3-1686-90, TU 1-1-0711-80, TU 14-1-4944-90
Sheets and strips	В33	TU 14-1-1930-77

Chemical composition

Standard	C	S	P	Mn	Cr	Si	Ni	Fe	Cu	V	Ti	Mo	W
GOST 4543-71	0.36-0.44	≤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
GOST 10702-78	0.36-0.44	≤0.035	≤0.035	0.5-0.8	0.45-0.75	≤0.2	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 of 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%. In accordance with the order, the content of Si = 0.10-0.37% can be established.

Mechanical properties

Section, mm	t отпуска, °C	s_T\|s_0,2, MPa	σ_U, MPa	d₅, %	y, %	KCU, kJ/m²	HB, MPa
Hot-rolled steel and hot rolled with special surface finish
-	-	-	-	-	-	-	≤179
Steel calibrated and calibrated with special surface finish
-	-	-	-	-	-	-	≤207
Quenching in water or oil from 820 °C to + leave at 500 °C, cooling in water or oil
≤25	-	785	980	11	45	677	-
Normalization at 870-925 °C + quenched in oil from 790 °C to + vacation at 540 °C
120	-	710	910	-	50	-	300
Quenching + tempering (forgings)
300-500	-	345	590	14	38	481	174-217
Quenching in oil with 820 °C
-	400	1220	1370	10	41	314	387
Normalization at 850 °C
-	-	-	790	18	48	-	-
Normalization at 870-925 °C + quenched in oil from 790 °C to + vacation at 540 °C
40	-	780	960	18	58	-	325
Quenching + tempering (forgings)
≤100	-	395	615	17	45	579	187-229
Quenching in oil with 820 °C
-	500	1080	1160	14	51	451	302
Normalization at 850 °C
-	-	-	750	-	50	-	-
Normalization at 870-925 °C + quenched in oil from 790 °C to + vacation at 540 °C
80	-	730	920	20	54	-	302
Quenching + tempering (forgings)
100-300	-	395	615	15	40	530	187-229
Quenching in oil with 820 °C
-	600	760	910	20	60	814	241
Normalization at 850 °C
-	-	-	690	20	-	-	-
Quenching + tempering (forgings)
300-500	-	395	615	13	35	481	187-229
Normalization at 850 °C
-	-	-	540	25	65	-	-
Quenching + tempering (forgings)
500-800	-	395	615	11	30	383	187-229
Normalization at 850 °C
-	-	-	480	25	79	-	-
Quenching + tempering (forgings)
≤100	-	440	635	16	45	579	197-235
Normalization at 850 °C
-	-	-	350	27	85	-	-
Quenching + tempering (forgings)
100-300	-	440	635	14	40	530	197-235
A sample with a diameter of 6 mm, length 30 mm, forged and normalized. The rate of deformation of 50 mm/min strain rate of 0.03 1/s.
-	-	-	225	36	92	-	-
Quenching + tempering (forgings)
300-500	-	440	635	13	35	481	197-235
A sample with a diameter of 6 mm, length 30 mm, forged and normalized. The rate of deformation of 50 mm/min strain rate of 0.03 1/s.
-	-	-	130	57	96	-	-
Quenching + tempering (forgings)
500-800	-	440	635	11	30	383	197-235
A sample with a diameter of 6 mm, length 30 mm, forged and normalized. The rate of deformation of 50 mm/min strain rate of 0.03 1/s.
-	-	-	91	71	100	-	-
Quenching + tempering (forgings)
≤100	-	490	655	16	45	579	212-248
A sample with a diameter of 6 mm, length 30 mm, forged and normalized. The rate of deformation of 50 mm/min strain rate of 0.03 1/s.
-	-	-	62	75	100	-	-
Quenching + tempering (forgings)
100-300	-	490	655	13	40	530	212-248
A sample with a diameter of 6 mm, length 30 mm, forged and normalized. The rate of deformation of 50 mm/min strain rate of 0.03 1/s.
-	-	-	45	76	100	-	-
Quenching + tempering (forgings)
≤100	-	540	685	15	45	579	223-262
A sample with a diameter of 6 mm, length 30 mm, forged and normalized. The rate of deformation of 50 mm/min strain rate of 0.03 1/s.
-	-	-	31	-	100	-	-
Quenching + tempering (forgings)
100-300	-	540	685	13	40	481	223-262
≤100	-	590	735	14	45	579	235-277
100-300	-	590	735	13	40	481	235-277
Normalization (forgings)
100-300	-	315	570	14	35	334	167-207
300-500	-	315	570	12	30	285	167-207
500-800	-	315	570	11	30	285	167-207

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
0	200	7820	-	-
20	200	7820	-	-
100	-	7800	44	118
200	-	7710	43	123
300	-	7840	41	134
400	-	7700	39	134
500	-	-	37	-
600	-	-	-	14

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. RDS, ADS submerged arc, electroslag welding. Necessary preheating and subsequent heat treatment.
Склонность к отпускной хрупкости	inclined
The temperature of forging	Start - 1250 °C, end - 830 °C. the cross Sections up to 50 mm are cooled in air, 50-200 mm - mulde, 201-300 mm - with oven.
Flock-sensitive sensitivity	highly sensitive
Machinability	In hot-rolled condition in NV 166-170 blower SB=690 MPa Kn TV.SPL.=1.0 Kn b.St.=0.9

Steel 40KHN

Designation

Description