Steel 02Н18К9М5Т (ЭП637А; VKS-210)

Designation

Name	The value
Designation GOST Cyrillic	02Н18К9М5Т
Designation GOST Latin	02H18K9M5T
Transliteration	02N18K9M5T
By chemical elements	02Н18Co9Mo5Ti

Name	The value
Designation GOST Cyrillic	ЭП637А
Designation GOST Latin	EP637A
Transliteration	EhP637A
By chemical elements	-

Name	The value
Designation GOST Cyrillic	ВКС-210
Designation GOST Latin	BKC-210
Transliteration	VKS-210
By chemical elements	WCoС-210

Description

02Н18К9М5Т steel is used: for the production of bodies of rocket motors, shafts, and other parts of aircraft engines, welded hulls, engines, gears, engines, parts artillery and infantry guns, hulls of submarines, submersibles, vessels large volumes of work at high pressure, highly loaded disks of turbomachines, gear wheels, spindles, parts of the worm pairs.

Note

Maraging high-alloy steel with higher structural stability in the interval of temperatures from cryogenic to 500 °C.

Standards

Name	Code	Standards
Bars and shapes	В22	GOST 1133-71, GOST 2590-2006, GOST 2591-2006
Sheets and strips	В33	GOST 4405-75
Classification, nomenclature and General rules	В20	OST 1 90005-91
Processing of metals by pressure. Forgings	В03	TU 14-1-1530-75
Bars and shapes	В32	TU 14-1-3039-80, TU 14-1-3051-80, TU 14-1-4211-87, TU 14-1-4896-90

Chemical composition

Standard	C	S	P	Mn	Cr	Si	Ni	Fe	Al	Ti	Mo	Co
TU 14-1-3039-80	≤0.02	≤0.01	≤0.01	≤0.1	-	≤0.1	17.7-19	Rest	≤0.15	0.5-0.8	4.6-5.5	8.5-9.5
TU 14-1-4211-87	≤0.02	≤0.01	≤0.01	≤0.1	≤0.3	≤0.1	17.7-19	Rest	≤0.15	0.5-0.8	4.6-5.5	8.5-9.5
TU 14-1-4896-90	≤0.02	≤0.01	≤0.01	≤0.1	≤0.3	≤0.1	17.7-19	Rest	≤0.15	0.6-0.8	4.6-5.5	8.5-9.5

Fe is the basis.
According to TU 14-1-4896-90 and TU 14-1-4211-87, the chemical composition is given for steel grade 02N18K9M5T-ID (EP637A-ID).
According to TU 14-1-4211-87 deviations from the chemical composition are allowed: for silicon and manganese, provided that their amount will not be more than 0.20%; by sulfur and phosphorus, provided that their sum is not more than 0.020%, for nickel minus 0.20%. A residual chromium content of up to 0.30% is allowed. Estimated content of modifiers and deoxidizers - magnesium, cerium, hafnium, germanium, boron, etc. is established by the supplier's technological instructions and their residual content in the metal is not determined by chemical analysis.
According to TU 14-1-3039-80 the chemical composition is given for steel grade 02N18K9M5T-EL (EP637A-EL). The calculated content of modifiers and deoxidizers: magnesium, hafnium, cerium, germanium and boron is established by the supplier's technological instructions and their residual content in the metal is not determined by chemical analysis. In the finished product, deviations in the sweat of the norms of the chemical composition are allowed: nickel -0.20%, silicon and manganese - not regulated, but the amount of their content should not exceed 0.20% sulfur and phosphorus - not regulated, but the amount of their content is not should exceed 0.020%. The residual chromium content should not exceed 0.30%.

Mechanical properties

Section, mm	s_T\|s_0,2, MPa	σ_U, MPa	y, %	KCU, kJ/m²	HRC
Gradation of performance properties of the finished heat-treated parts for OST 1 90005-91
-	-	1910-2110	-	-	49.5-54
-	-	1910-2160	-	-	49.5-54
Bars and rods, hot-rolled 02Н18К9М5Т-EL (ЭП637А-EL, ВКС210-EL) on the other 14-1-3039-80. Annealing in air 780-820 °C (aging 1 HR) + Aging at 500-520 °C (extract 3 hours), air cooling
	-	≥1913	≥47	≥290	-
The wrought-iron bars on the other 14-1-4211-87. Quenching in water with 1170-1220 °C (exposure 1-2 h) + 3-fold quenching in water from 900-930 °C (exposure 1-2 h) + Annealing in air or in water 780-820 °C (exposure 1-2 h) + Aging at 500-540 °C (delay of 2-5 h), air cooling (in the column of the delivery condition specified cut direction samples)
-	≥1765	≥1810	≥25	≥240	-
-	≥1765	≥1810	≥40	≥340	-

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
y	The relative narrowing
KCU	Toughness
HRC	Rockwell hardness (indenter diamond spheroconical)

Technological properties

Name	The value
Macrostructure and pollution	The macrostructure of the steel on the other 14-1-3039-80 should not have shrinkage and looseness, bubbles, cracks, inclusions, crusts, delamination and placenow visible without using the magnifying devices.