Steel 40 (40A)

Designation

Name	The value
Designation GOST Cyrillic	40
Designation GOST Latin	40
Transliteration	40
By chemical elements	40

Name	The value
Designation GOST Cyrillic	40А
Designation GOST Latin	40A
Transliteration	40A
By chemical elements	40

Description

40 steel is used: for the manufacture of sheet metal, 1−2 mm 4−14 category, intended for cold forming; crankshafts, connecting rods, gear rims, flywheels, gears, bolts, axles and other parts after the improvement; shafts and extension shafts of the generators; medium sized workpieces, which are requirements of high surface hardness and high wear resistance at low strain (long shafts, chassis, rollers, gears) after surface hardening with heating HDTV; details of pipeline valves after quenching and tempering; hot-rolled strip profile with a bias for agricultural machinery; of forgings of shafts of compressors and gas turbines (steel 40A); the wire used for the manufacture of spokes of motorcycles and bicycles.

Note

The degree of deoxidation — SP.

Standards

Name	Code	Standards
Bars and shapes	В32	GOST 1050-88, GOST 7417-75, GOST 8559-75, GOST 8560-78, GOST 10702-78, GOST 14955-77, GOST 1050-2013, TU 14-1-5414-2001, TU 14-1-1209-74, TU 14-1-1629-76, TU 14-1-2118-77, TU 14-1-495-73, TU 14-1-701-73, TU 14-1-866-74, TU 14-11-245-88, STP М323-80, TU 14-1-2252-2007, TU 14-1-1271-75, TU 14-1-5228-93, TU 14-136-367-2008
Bars and shapes	В22	GOST 1133-71, GOST 8239-89, GOST 8240-97, GOST 8278-83, GOST 8281-80, GOST 8282-83, GOST 8283-93, GOST 8319.0-75, GOST 8319.5-75, GOST 8319.8-75, GOST 8319.11-75, GOST 8319.12-75, GOST 8509-93, GOST 8510-86, GOST 9234-74, GOST 11474-76, GOST 12492.15-90, GOST 2590-2006, GOST 2591-2006, GOST 2879-2006, OST 5.9087-84, STP М326-80
Fittings, components and parts for railway rolling stock	Д55	GOST 11530-93
Sheets and strips	В33	GOST 1577-93, GOST 4041-71, TU 14-125-661-93, TU 14-1-4516-88, TU 114-125-661-93
Tape	В34	GOST 2284-79, GOST 10234-77
Steel wire medium and high carbon	В72	GOST 3110-74, GOST 3920-70, GOST 7372-79, GOST 9389-75, GOST 9850-72, GOST 17305-91, GOST 26366-84
Steel pipes and fittings to them	В62	GOST 3262-75, GOST 20295-85, GOST 24950-81, TU 14-3-1428-86
Tape	В24	GOST 3560-73
Low carbon steel wire	В71	GOST 5663-79
Sheets and strips	В23	GOST 82-70, GOST 14918-80, GOST 16523-97, GOST 16523-89, GOST 16523-70, GOST 103-2006, GOST 19903-90, TU 14-1-486-73, TU 14-1-1934-76, TU 14-1-4632-93
Processing of metals by pressure. Forgings	В03	GOST 8479-70, TU 302.02.173-93, TU НЗЛ 342-89, ST ЦКБА 010-2004
Blanks. Of the workpiece. Slabs	В31	OST 3-1686-90, TU 108.11.890-87, TU 14-1-4944-90, STP М322-90
Thermal and thermochemical treatment of metals	В04	ST ЦКБА 026-2005

Chemical composition

Standard	C	S	P	Mn	Cr	Si	Ni	Fe	Cu	N	As
GOST 1050-88	0.37-0.45	≤0.04	≤0.035	0.5-0.8	≤0.25	0.17-0.37	≤0.3	Rest	≤0.3	≤0.006	≤0.08
GOST 10702-78	0.37-0.45	≤0.04	≤0.035	≤0.6	≤0.25	≤0.2	≤0.3	Rest	≤0.3	≤0.006	≤0.08
TU НЗЛ 342-89	0.37-0.45	≤0.03	≤0.03	0.5-0.8	≤0.25	0.17-0.37	≤0.3	Rest	≤0.3	-	-

Fe is the basis.
According to GOST 1050-88 and GOST 10702-78 the chemical composition is given for steel grade 40.
According to GOST 1050-88, the nitrogen content is specified for the steel of the oxygen-converter method of smelting. For all other types of smelting, the nitrogen content was N≤0.008%.
TU NZL 342-89 chemical composition is given for steel grade 40A.

Mechanical properties

Section, mm	t отпуска, °C	s_T\|s_0,2, MPa	σ_U, MPa	d₅, %	d₄	d	d₁₀	y, %	KCU, kJ/m²	HB, MPa	HRB
Tape flatted average strength of 0.1-4.0 mm according to GOST 10234-77 in the state of delivery (indicated delivery)
-	-	-	640-980	-	-	-	-	-	-	-	-
-	-	-	640-780	-	-	-	-	-	-	-	-
-	-	-	780-930	-	-	-	-	-	-	-	-
-	-	-	≤690	-	-	≥10	-	-	-	-	-
-	-	-	≤490	-	-	-	-	-	-	-	-
Rolled sheet 1-2 categories of heat-treated (annealing, normalization, high tempering or normalizing + tempering) in the delivery state according to GOST 4041-71
4-14	-	-	510-660	≥21	-	-	≥17	-	-	≤167	≤85
Wire for cold heading as supplied by GOST 5663-79
-	-	-	560-710	-	-	-	-	≥55	-	-	-
-	-	-	≤740	-	-	-	-	≥40	-	-	-
Hot-rolled steel and hot rolled with special surface finish
-	-	-	-	-	-	-	-	-	-	≤217	-
-	-	-	-	-	-	-	-	-	-	≤163	-
Steel calibrated and calibrated with special surface finish
-	-	-	-	-	-	-	-	-	-	≤217	-
-	-	-	≤590	-	-	-	-	-	-	≤197	-
Sheet
80	-	-	≥560	≥20	-	-	-	-	-	-	-
80	-	-	≥520	≥21	-	-	-	-	-	-	-
4-14	-	-	510-650	≥21	-	-	-	-	-	≤167	-
Tape
0.1-4	-	-	450-700	-	≥14	-	-	-	-	-	-
0.1-4	-	-	850-1050	-	-	-	-	-	-	-	-
Cold-rolled steel strip of 0.1-4.0 mm in the delivery state according to GOST 2284-79
-	-	-	690-1030	-	-	-	-	-	-	-	-
-	-	-	440-690	-	≥14	-	-	-	-	-	-
-	-	-	440-600	-	≥14	-	-	-	-	-	-
Steel grooved 5-th category
-	-	-	≥610	≥6	-	-	-	≥35	-	-	-
-	-	-	≥510	≥14	-	-	-	≥40	-	-	-
Forgings. Hardening + Vacation
300-500	-	≥275	≥530	≥15	-	-	-	≥32	≥290	156-197	-
500-800	-	≥275	≥530	≥13	-	-	-	≥30	≥290	156-197	-
100-300	-	≥315	≥570	≥14	-	-	-	≥35	≥340	167-207	-
100	-	≥345	≥590	≥18	-	-	-	≥45	≥590	174-217	-
Forgings. Normalization
300-500	-	≥215	≥430	≥18	-	-	-	≥40	≥440	123-167	-
500-800	-	≥215	≥430	≥16	-	-	-	≥35	≥390	123-167	-
100-300	-	≥245	≥470	≥19	-	-	-	≥42	≥390	143-179	-
300-500	-	≥245	≥470	≥17	-	-	-	≥35	≥340	143-179	-
100-300	-	≥275	≥530	≥17	-	-	-	≥38	≥340	156-197	-
100	-	≥275	≥530	≥20	-	-	-	≥40	≥440	156-197	-
Hot-rolled sheet in the delivery condition. Group strength К490В
≤2	-	-	490-720	-	≥12	-	-	-	-	-	-
2-3.9	-	-	490-720	-	≥13	-	-	-	-	-	-
Cold-rolled sheet in the delivery condition. Group strength К490В
≤2	-	-	490-720	-	≥13	-	-	-	-	-	-
2-3.9	-	-	490-720	-	≥14	-	-	-	-	-	-
Forged billet shafts of compressors and gas turbines, heat-treated in the delivery condition on the other NZL 342-89 (longitudinal samples, in the column of the delivery condition specified strength)
≤400	-	≥274	≥509	≥17	-	-	-	≥35	≥343	-	-
Rolled without heat treatment - delivery condition
60	-	-	≥570	≥20	-	-	-	-	-	-	-
6-25	-	-	≥570	≥19	-	-	-	≥45	-	-	-
80	-	≥340	≥580	≥19	-	-	-	≥45	≥589	-	-
-	-	≥340	≥600	≥16	-	-	-	-	-	-	-
-	-	≥320	≥580	≥17	-	-	-	-	-	-	-
Rolled steel and punching. Quenching in water from 830-850 °C (exposure for 2.5-4.0 hours depending on the thickness and weight of the workpiece) + Vacation
≤100	580-640	≥345	≥590	≥18	-	-	-	≥45	≥588	174-217	-
Rolled steel and punching. Annealing in air from 870-890 °C (exposure for 2.5-4.0 hours depending on the thickness and weight of the workpiece)
≤300	-	≥275	≥530	≥17	-	-	-	≥38	≥343	156-197	-
Steel, hot-rolled, forged, calibrated and silverfish 2nd category after normalization
≤25	-	-	≥570	≥19	-	-	-	≥45	≥579	-	-
Rolled steel. Hardening + Vacation
-	200	≥750	≥930	≥7	-	-	-	≥45	-	≥267	-
-	300	≥710	≥860	≥8	-	-	-	≥51	-	≥247	-
-	400	≥640	≥790	≥10	-	-	-	≥57	-	≥225	-
-	500	≥550	≥730	≥12	-	-	-	≥62	-	≥208	-
-	600	≥450	≥660	≥16	-	-	-	≥66	-	≥188	-
-	700	≥380	≥620	≥17	-	-	-	≥71	-	≥170	-
A sample with a diameter of 6 mm and a length of 30 mm, laminated. Strain rate 16 mm/min strain Rate of 0.009 1/s
-	-	≥99	≥140	≥48	-	-	-	≥85	-	-	-
-	-	≥70	≥110	≥53	-	-	-	≥97	-	-	-
-	-	≥54	≥71	≥55	-	-	-	≥100	-	-	-
-	-	≥28	≥58	≥69	-	-	-	≥100	-	-	-
-	-	≥24	≥37	≥60	-	-	-	≥100	-	-	-
-	-	≥16	≥26	≥87	-	-	-	≥100	-	-	-
-	-	≥12	≥18	≥56	-	-	-	≥100	-	-	-

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
d₄	Elongation after rupture
d	Elongation after rupture
d₁₀	Elongation after rupture
y	The relative narrowing
KCU	Toughness
HB	Brinell hardness number
HRB	Rockwell hardness (indenter steel, spherical)

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)
20	213	-	7850	515	160	-	483
200	201	78	-	48	296	128	497
400	176	68	-	42	493	141	529
700	131	50	-	30	932	152	628
800	118	45	-	25	1110	125	674

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
a	The coefficient of linear expansion
С	Specific heat

Technological properties

Name	The value
Weldability	Limited weldability. The welding methods of SMAW, ADS submerged arc and gas protection electroslag welding. Recommended heating and subsequent heat treatment. The CCC without restriction.
Склонность к отпускной хрупкости	Tend not.
The temperature of forging	Start - 1250 °C, the end - of 800 °C. the cooling of the workpiece cross-section up to 400 mm in air.
Flock-sensitive sensitivity	not sensitive.
Machinability	In the hot rolled condition with a HB of 170 and blower SB=520 MPa Kn TV.SPL.=1.2 Kn b.St.=1.05
Surfacing	Surfacing of sealing surfaces of valves in accordance with OST 26-07-2028-81 is made by manual arc welding electrodes type e-20X13 with plaster SSSI-13НЖ, NII-48, NII-48Ж-1 or SV wire-12H13 or SV-20X13. Surface preparation for overlay welding is performed by machining. Surfacing is performed with preliminary and accompanying heating to 400-450 °C is not less than 3 layers with thickness not less than 4 mm, excluding allowance for machining. Heat treatment after welding is produced by tempering at 550-600 °C (delay of 2-5 h) hardness HB=301-350, at 600-650 °C (delay of 2-5 h) hardness HB=240 to 300, at 400-450 °C (delay of 2-5 h) hardness HB=351-400. The temperature of the furnace when loading the details for the home should be no more than 300 °C.