Steel 08KH17N5M3 (ЭИ925)

Designation

Name	The value
Designation GOST Cyrillic	08Х17Н5М3
Designation GOST Latin	08X17H5M3
Transliteration	08H17N5M3
By chemical elements	08Cr17Н5Mo3

Name	The value
Designation GOST Cyrillic	ЭИ925
Designation GOST Latin	EI925
Transliteration	EhI925
By chemical elements	-

Description

08KH17N5M3 steel is used: for the manufacture of products, working in atmospheric conditions, acetate, sulfate and other saline environments; elastic elements; welding wire used for welding parts and welding of steel structures in energy engineering; welding electrodes.

Note

Stainless steel austenitic-martensitic class.

Standards

Name	Code	Standards
Processing of metals by pressure. Forgings	В03	GOST 25054-81
Tape	В34	GOST 4986-79, TU 14-1-2410-78
Sheets and strips	В33	GOST 5582-75, TU 14-1-2127-77, TU 14-1-2128-77, TU 14-1-2186-77, TU 14-1-2476-78
Classification, nomenclature and General rules	В30	GOST 5632-72
Classification, nomenclature and General rules	В20	OST 1 90005-91
Blanks. Of the workpiece. Slabs	В31	OST 3-1686-90, TU 14-1-1213-75, TU 14-1-1214-75
Thermal and thermochemical treatment of metals	В04	STP 26.260.484-2004
Bars and shapes	В32	TU 14-1-1831-76, TU 14-11-245-88
Welding and cutting metals. Soldering, riveting	В05	TU 14-1-997-74, TU 14-1-997-2012

Chemical composition

Standard	C	S	P	Mn	Cr	Si	Ni	Fe	Cu	V	Ti	Mo	W
TU 14-1-997-74	0.06-0.1	≤0.02	≤0.035	≤0.8	16-17.5	≤0.8	4.5-5.5	Rest	≤0.2	-	-	3-3.5	-
GOST 5632-72	0.06-0.1	≤0.02	≤0.035	≤0.8	16-17.5	≤0.8	4.5-5.5	Rest	≤0.3	≤0.2	≤0.05	3-3.5	≤0.2
TU 14-1-2410-78	0.06-0.1	≤0.02	≤0.035	≤0.7	16-17.5	≤0.7	4.5-5.5	Rest	-	-	-	3-3.5	-
TU 14-1-2186-77	0.06-0.1	≤0.02	≤0.035	≤0.7	16-17.5	≤0.7	4.5-5.5	Rest	≤0.3	≤0.2	≤0.05	3-3.5	≤0.2

Fe is the basis.
According to TU 14-1-1831-76, deviations in chemical composition are allowed: for molybdenum ± 0.020%, for carbon + 0.010%, for chromium + 0.10 / -0.50%, for nickel + 0.50%. The content of elements guaranteed by the supplier in accordance with the requirements of GOST 5632 is allowed, except for vanadium, the content of which is allowed not more than 0.10% and titanium, the content of which is allowed not more than 0.10%.
According to TU 14-1-2410-78, the chemical composition is presented for steel grade 08X17N5M3 (EI925). The mass fraction of residual elements is allowed in accordance with GOST 5632. If all the requirements of technical specifications are met in the finished product, deviations in chemical composition from the norms are allowed: by chroma ± 0.10%, nickel ± 0.10%, molybdenum ± 0.020%.

Mechanical properties

Section, mm	s_T\|s_0,2, MPa	σ_U, MPa	d₅, %	d₄	y, %	KCU, kJ/m²	HB, MPa	HRC
Gradation of performance properties of the finished heat-treated parts for OST 1 90005-91
-	-	1180-1370	-	-	-	-	341-388	37-41
Cold-rolled steel strip of 0.05-2.00 mm according to GOST 4986-79 in the delivery condition. Samples. Vacation at 440-460 °C (aging 1 HR)
0.2-2	-	≥1230	-	≥4	-	-	-	-
0.2	-	≥1230	-	≥2	-	-	-	-
0.2-2	-	≥1130	-	≥6	-	-	-	-
0.2	-	≥1130	-	≥3	-	-	-	-
Cold-rolled steel strip of 0.05-2.00 mm according to GOST 4986-79. Normalization at 1030-1070 °C (samples)
0.2-2	-	≤1130	-	≥16	-	-	-	-
0.2	-	≤1130	-	≥8	-	-	-	-
Cold-rolled steel strip of 0.05-2.00 mm according to GOST 4986-79. Normalization at 940-960 °C, cold treatment at -70 °C (exposure 2 hours) + Vacation at 440-460 °C (exposure for 1 h) (samples)
0.2-2	-	≥1180	-	≥6	-	-	-	-
0.2	-	≥1180	-	≥3	-	-	-	-
Sheet thin cold-rolled. Normalization at 1030-1080 °C
0.5-0.8	≥343	≥880	≥18	-	-	-	-	-
Hot rolled sheet (of 1.5-3.9 mm) and cold rolled (0,7-3,9 mm) steel according to GOST 5582-75. Quenching in water or air from 1030-1080 °C
-	≥610	≤1180	≥20	-	-	-	-	-
Hot rolled sheet (of 1.5-3.9 mm) and cold rolled (0,7-3,9 mm) steel according to GOST 5582-75. Annealing in air or in water 930-950 °C, cold treatment at minus 70 °C for 2 h+ Vacation at 440-460 °C (aging for 1 h), air cooling
	≥885	≥1180	≥9	-	-	-	-	-
Forgings. Annealing in air from 1030-1080 °C
≤1000	≥833	≥1176	≥10	-	≥35	≥392	-	-
Bars hot rolled and forged on the other 14-1-1831-76. Longitudinal samples: Annealing in air or in water from 940-960 °C, cold treatment at minus 70 °C for 2 hours+ aged at 440-460 °C (aging for 1 h), air cooling
	≥850	≥1200	≥12	-	≥50	≥490	-	-
Bars hot rolled and forged at STP 26.260.484-2004. Quenching in water or air from 980-1020 °C, cold treatment at -70 °C (aged for at least 2 h) + Aging at 350-380 °C, air cooling
	≥850	≥1200	≥12	-	≥50	≥392	-	-

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

Technological properties

Name	The value
Weldability	Without restrictions.
Macrostructure and pollution	Macrostructure of steel shall be no traces of shrinkage, delamination, foreign inclusions.
Features of heat treatment	After quenching, the steel has a structure of unstable austenite with a small amount of martensite. In this state, the steel doesn't strengthen aging. Hardening as a result of ageing after pre-deformation or cold treatment products that causes the formation of martensite. Parts, components and apparatus made of nettervibration sheets, strips, extruded profiles, as well as from bars, rods and forgings, are subjected to full cycle of hardening heat treatment: a) annealing (for obtaining a structure of austenite); b) cold treatment at minus 70 °C (aging for at least 2 h, while cooling in the refrigerating chamber, the exposure time is doubled); C) aging (to achieve a specified level of properties). Products, to achieve maximum corrosion resistance, is subjected to heat treatment by mode: heating to 1000±20 °C, exposure with wall thickness up to 15 mm - 30 min; more than 15 mm - 30 min + 1-2 min per 1 mm of maximum wall thickness; cooling in water or air; cold treatment; aging at 350-380 °C, dwell time 1 hour + 1 min per 1 mm cross section; the cooling air. To obtain maximum strength characteristics of aging must be carried out at 400-480 °C, dwell time 1 hour + 1 min per 1 mm cross section, but the steel acquires the tendency to intergranular corrosion. In the hardening of products with wall thickness up to 8 mm, the cooling is carried out on the tranquil air, the products wall thickness more than 8 mm, and also products from bar and forgings are cooled in water. Slow cooling of products (with oven or in bulk) are not allowed. The gap between the operations of quenching and cold treatment should not exceed 12h. Before cold processing products shall not be subjected to heating or exposure to temperatures from 0 to minus 40 °C. cooling Time of the product from room temperature to minus 70 °C should be minimal. When obtaining low values of relative narrowing and toughness in comparison with specified in the normative documents, what is usually observed in large forgings, it is recommended obezvrezivate annealing regime: heating to 500±10 °C , exposure 30 h for sections up to 50 mm and 50 h for sections more than 50 mm. the Highest rate of bezodiazepine observed in the martensitic structure, so before bezodiazepines structure of the steel is transferred to a martensitic state by heat treatment at minus 70 °C. To obtain the desired properties after obezbolivaushee heat treatment necessary heat treatment for hardening of the regime *.