Steel 70S3A

Designation

Steel 70S3A used: for the production of heavily loaded springs responsible and osobochistogo destination.

Steel spring alloy of high quality.

Name	Code	Standards
Sheets and strips	В23	GOST 103-2006
Bars and shapes	В22	GOST 1133-71, GOST 2590-2006, GOST 2591-2006, GOST 2879-2006
Wire, steel, alloy	В73	GOST 14963-78
Steel wire medium and high carbon	В72	GOST 26366-84
Sheets and strips	В33	GOST 4405-75
Bars and shapes	В32	GOST 7417-75, GOST 7419-90, GOST 8559-75, GOST 8560-78, GOST 14955-77, GOST 14959-79, TU 14-1-2118-77, TU 14-178-179-88, TU 14-11-245-88, TU 14-136-367-2008

Standard	C	S	P	Mn	Cr	Si	Ni	Fe	Cu
GOST 14959-79	0.66-0.74	≤0.025	≤0.025	0.6-0.9	≤0.3	2.4-2.8	≤0.25	Rest	≤0.2

Fe is the basis.

Section, mm	t отпуска, °C	s_T\|s_0,2, MPa	σ_U, MPa	d₅, %	y, %	KCU, kJ/m²	HB, MPa	HRC
Wire with special surface finishes for the manufacture of springs cold-wound in the delivery condition according to GOST 14963-78
0.5-14	-	-	≤1030	-	-	-	-	-
Forgings section 16-25 mm. Annealing + Quenching in oil from 900 °C + Vacation
-	250	≥1520	≥1740	-	≥10	-	-	≥60
Rolled steel. Hardened in oil from 830 °C to + Vacation at 450 °C
-	-	≥1540	≥1780	≥10	-	≥235	-	-
Forgings section 16-25 mm. Annealing + Quenching in oil from 900 °C + Vacation
-	350	≥1520	≥1740	≥7	≥17	≥265	-	≥56
Rolled steel. Hardened in oil from 830 °C to + Vacation at 450 °C
-	-	≥1440	≥1710	≥12	≥32	≥285	-	-
Spring. Annealing at 840-850 °C. Wrapped at 850-880 °C. Quenching in oil 850-880 °C + Vacation at 460-470 °C
-	-	-	-	-	-	-	388-445	-
Rod forged. Annealing + Isothermal quenching from 900 °C with a hold at 320 °C
15-16	-	-	≥1060	≥2	≥13	-	-	≥60
Forgings section 16-25 mm. Annealing + Quenching in oil from 900 °C + Vacation
-	450	≥1220	≥1690	≥6	-	≥363	-	≥49
Rolled steel. Hardened in oil from 830 °C to + Vacation at 450 °C
-	-	≥1270	≥1620	≥16	≥32	-	-	-
Rod forged. Annealing + Isothermal quenching from 900 °C with a hold at 340 °C
15-16	-	-	≥1270	≥4	≥15	-	-	≥49
Rolled steel. Hardened in oil from 830 °C to + Vacation at 450 °C
-	-	≥1220	≥1400	≥20	≥65	-	-	-
Rolled steel. Steel categories: 3, 3A, 3B, 3C, 3D, 4, 4A, 4B. Quenching in oil from 850 °C + Vacation at 470 °C
	-	≥1470	≥1670	≥6	≥25	-	-	-

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)

Temperature	Е, HPa	G, HPa	l, W/(m · °C)	a, 10^-6 1/°C	С, J/(kg · °C)
20	214	83	25	-	-
100	208	81	26	114	480
200	198	76	27	123	510
300	192	79	28	128	520
400	185	69	29	133	535
500	180	67	29	137	565
600	152	57	29	141	585
700	139	52	28	143	620
800	132	49	27	143	620
1000	-	-	-	128	700

Name	Description
Е	The normal elasticity modulus
G	Modulus of elasticity shear torsion
r	Density
l	Coefficient of thermal conductivity
R	UD. the resistivity

Name	The value
Weldability	Does not apply to welded structures.
Склонность к отпускной хрупкости	Inclined.
The temperature of forging	Start - 1100 °C, the end - of 800 °C.
Flock-sensitive sensitivity	not sensitive.