08Х18Н5Г12АБ steel is used: for the production of rolled products, forgings and stampings used in the manufacture of parts in shipbuilding and ship repairs; hull structures of ships, vessels and goods marine equipment (propeller shaft low-speed gear, axles, spindles, slides, shafts, couplings, rods, cylinders, brackets).

Note

Corrosion resistant, low steel high-strength austenitic.
When cold deformation is not more than 75%, the magnetic permeability μ ≤ 1,01 GS/C. Heat treatment on the magnetic permeability is not affected.

Standards

Name	Code	Standards
Processing of metals by pressure. Forgings	В03	OST 5Р.9125-84
Castings, non-ferrous metals and alloys	В84	RD 9257-76
Bars and shapes	В32	TU 14-1-784-73
Blanks. Of the workpiece. Slabs	В31	TU 14-1-853-74
Castings with special properties (iron and steel)	В83	TU 5.961-11131-79

Chemical composition

Standard	C	S	P	Mn	Cr	Si	Ni	Fe	Cu	N	V	Mo	W	Co
TU 5.961-11131-79	≤0.08	≤0.03	≤0.045	11.5-13.5	18-19.5	≤0.8	4.5-5.5	Rest	-	0.45-0.52	0.2-0.35	-	-	-
TU 14-1-784-73	≤0.08	≤0.03	≤0.045	11.5-13.5	18-19.5	≤0.8	4.5-5.5	Rest	≤0.3	0.45-0.52	0.2-0.35	≤0.3	≤0.3	≤0.3

Fe is the basis.
According to RD 9257-76, TU 14-1-853-74 and TU 5.961-11131-79 the total content of Nb + Ta = 0.80-1.10%.
According to TU 14-1-853-74, deviations from the content of elements according to the chemical composition of steel are possible: 08Х18Н5Г12АБ (НН-3Б): carbon +0.010%, manganese + 0.50%, nickel + 0.50%, chromium + 0.50%, vanadium +0.10%, niobium +0.10%, nitrogen +0.030%, phosphorus +0.0050%, silicon + 0.20%. The residual content of elements in the chemical composition of the steel should not exceed: copper, cobalt, tungsten and molybdenum 0.30% of each element.
According to TU 14-1-784-73, the chemical composition is given for steel grade 08H18N5G12AB (NN-3B). The total content of Niobium (Nb) + Tantalum (Ta) should be in the range of 0.80-1.10%. Deviations in chemical composition are allowed: for carbon +0.010%, for manganese + 0.50%, for nickel + 0.50%, for chromium + 0.50%, for niobium +0.10%, for silicon +0.20 %, in nitrogen +0,030%, in phosphorus +0,0050%, in vanadium +0,10%. The residual content of elements in the chemical composition of the steel should not exceed: copper, cobalt, tungsten and molybdenum 0.30 each.

Mechanical properties

Section, mm	s_T\|s_0,2, MPa	σ_U, MPa	d₅, %	KCU, kJ/m²	HB, MPa
Hot rods and forgings of round and square. Quenching in water or air from 950-980 °C
≤180	≥441	≥687	≥25	≥588	-
Forgings for parts resistant to the ICC. Quenching in oil or air from 950-1050 °C
300	≥441	≥687	≥25	≥590	187-240
Bars hot rolled and forged, round and square. Quenching in water from 900-1050 °C
≤180	≥490	≥736	≥25	≥588	-

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
KCU	Toughness
HB	Brinell hardness number

Physical characteristics

Temperature	r, kg/m³	l, W/(m · °C)	a, 10^-6 1/°C
20	7800	1675	-
100	-	-	1670
1000	-	-	2100

A description of the physical symbols

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

Technological properties

Name	The value
Weldability	Welding is not performed.
Machinability	Machinability similar to steel grades 12Х18Н12Т and 08KH18N12T.
Macrostructure and pollution	Macrostructure of steel bars on the other 14-1-784-73 should not have shrinkage, bubbles, cracks, inclusions, visible without using the magnifying devices.

Steel 08Х18Н5Г12АБ (NN-3B)

Designation

Description