12KHN steel is used: for manufacturing of gear rims, gear wheels, fingers and other critical parts operating under conditions of shock and alternating loads; circular grooved and grinded rolled in coils for the manufacture of parts of automobiles by cold upsetting; tools and accessories at the Volga automobile plant by type, used by «FIAT».

Note

The structural quality steel chrome-Nickel.

Standards

Name	Code	Standards
Bars and shapes	В32	GOST 4543-71, GOST 7417-75, GOST 10702-78, GOST 14955-77, TU 14-1-5414-2001, TU 14-1-2078-77, TU 14-1-2118-77, TU 14-1-4597-89, TU 14-1-794-73, TU 14-1-3260-81, TU 14-11-245-88, TU 14-1-1271-75, TU 14-136-367-2008
Bars and shapes	В22	GOST 8319.0-75
Blanks. Of the workpiece. Slabs	В31	OST 3-1686-90, TU 14-1-4944-90, TU 14-1-904-74, TU 14-1-993-74
Sheets and strips	В33	TU 14-1-518-73, TU 14-1-635-73
Tape	В34	TU 3-85-80, TU 14-4-103-73

Chemical composition

Standard	C	S	P	Mn	Cr	Si	Ni	Fe	Cu	V	Ti	Mo	W
TU 14-1-518-73	0.09-0.15	≤0.035	≤0.035	0.3-0.6	0.4-0.7	0.17-0.37	0.5-0.8	Rest	-	-	-	-	-
GOST 4543-71	0.09-0.15	≤0.035	≤0.035	0.3-0.6	0.4-0.7	0.17-0.37	0.5-0.8	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%.
According to TU 14-1-993-74 the chemical composition is given for steel grade 12ХН. Permissible deviations from the standards for chemical composition: carbon ± 0.010%, manganese, chromium and silicon ± 0.020% each, nickel ± 0.030%, sulfur and phosphorus ± 0.0050% each.
According to TU 14-1-518-73, the total content of sulfur and phosphorus in the steel should not be more than 0.060%. In the finished rolled products, if all the requirements of the technical specifications are met, deviations from the chemical composition standards are allowed in accordance with Table 3 of GOST 4543.

Mechanical properties

Section, mm	s_T\|s_0,2, MPa	σ_U, MPa	d₅, %	y, %	KCU, kJ/m²	HB, MPa
Steel calibrated and calibrated with special surface finish
-	-	-	-	-	-	≤210
-	-	410-530	-	≥70	-	-
-	-	410-510	-	≥70	-	-
Rental and calibrated with special surface finish. After a holiday or a conventional annealing
	-	410-530	-	≥70	-	-
Rolled calibrated, honed and calibrated with special surface finish. After spheroidizing annealing
	-	410-510	≥28	≥70	-	120-150
Rolled calibrated round (5-21 mm) and machined (13,5-21,0) and in reels. Quenching in water from 900-920 °C + vacation at 150-180 °C, air cooling
	≥590	≥830	≥8	-	≥690	-
Rolled calibrated round (5-21 mm) and machined (13,5-21,0) and in reels. Quenching in oil from 900-920 °C + vacation at 150-180 °C, air cooling
	≥440	≥640	≥10	-	≥880	-
Rolled calibrated round (5-21 mm) and machined (13,5-21,0) and in reels. Full hard
5-21	-	-	-	-	-	≤163
High-quality and sheet hire. Quenching in water from 910±10 °C + Vacation at 150-180 °C, air cooling
25	≥440	≥640	≥10	-	≥883	≤200

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

Technological properties

Name	The value
Macrostructure and pollution	The macrostructure of the steel when checking on the etched transverse templeto should not have shrinkage looseness, blistering, delamination, cracks, inclusions and placenow.
Microstructure	Harvesting on the other 14-1-993-74 should be supplied with a grain size not larger than 5 rooms, allowed the presence of small quantities of grains the 3. Depth bezoperatsionnogo layer in the workpiece (ferrite + transition zone) must not exceed 1.5% per side.

Steel 12KHN

Designation

Description